Phase noise cancellation method and apparatus

ABSTRACT

Provided are a method for estimating and compensating for phase noise using a phase tracking reference signal in a wireless communication system, and an apparatus using the method.

BACKGROUND OF THE DISCLOSURE Field of the Disclosure

This disclosure relates to wireless communication.

Related Art

As more and more communication devices require more communicationcapacity, there is a need for improved mobile broadband communicationover existing radio access technology. Also, massive machine typecommunications (MTC), which provides various services by connecting manydevices and objects, is one of the major issues to be considered in thenext generation communication. In addition, communication system designconsidering reliability/latency sensitive service/UE is being discussed.The introduction of next generation radio access technology consideringenhanced mobile broadband communication (eMBB), massive MTC (mMTC),ultra-reliable and low latency communication (URLLC) is discussed. Thisnew technology may be called new radio access technology (new RAT or NR)in the present disclosure for convenience.

In the process of implementing wireless communication in thehigh-frequency region of mmWave or higher, the effect of phase noise hada great effect on reception performance, and countermeasures weresuggested. However, this method is expected to show limitations in theTHz band, and a corresponding appropriate method is required.

SUMMARY OF THE DISCLOSURE

A method of generating a signal for efficiently controlling phase noisein a transmission/reception operation of a physical layer of wirelesscommunication and a reception method thereof are proposed. Specifically,the present disclosure proposes a method of estimating in the frequencydomain and removing it in the time domain in order to effectively removethe phase noise characteristic in the THz band.

According to the present disclosure, it is possible to efficientlyestimate and compensate for phase noise in the THz band. Specifically,through the arrangement of a phase tracking reference signal (PTRS)proposed in the present disclosure and phase noise estimation andcompensation based thereon, while minimizing the implementationcomplexity of the receiving end, more efficient phase noise compensationin the THz band is possible.

Effects that can be obtained through specific examples of the presentspecification are not limited to the effects listed above. For example,various technical effects that a person having ordinary skill in therelated art can understand or derive from this specification may exist.Accordingly, the specific effects of the present specification are notlimited to those explicitly described herein, and may include variouseffects that can be understood or derived from the technicalcharacteristics of the present specification.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a wireless communication system to which the presentdisclosure can be applied.

FIG. 2 is a diagram showing a wireless protocol architecture for a userplane.

FIG. 3 is a diagram showing a wireless protocol architecture for acontrol plane.

FIG. 4 shows another example of a wireless communication system to whichthe technical features of the present disclosure can be applied.

FIG. 5 illustrates a functional division between an NG-RAN and a 5GC.

FIG. 6 illustrates an example of a frame structure that may be appliedin NR.

FIG. 7 illustrates a slot structure.

FIG. 8 illustrates CORESET.

FIG. 9 is a diagram illustrating a difference between a related artcontrol region and the CORESET in NR.

FIG. 10 illustrates an example of a frame structure for new radio accesstechnology.

FIG. 11 illustrates a structure of a self-contained slot.

FIG. 12 is an abstract schematic diagram of a hybrid beamformingstructure in terms of a TXRU and a physical antenna.

FIG. 13 shows a synchronization signal and a PBCH (SS/PBCH) block.

FIG. 14 is for explaining a method for a UE to obtain timinginformation.

FIG. 15 shows an example of a process of acquiring system information ofa UE.

FIG. 16 is for explaining a random access procedure.

FIG. 17 is a diagram for describing a power ramping counter.

FIG. 18 is for explaining the concept of the threshold value of the SSblock for the RACH resource relationship.

FIG. 19 is a flowchart illustrating an example of performing an idlemode DRX operation.

FIG. 20 illustrates a DRX cycle.

FIG. 21 shows an example of the arrangement of PTRS that can be appliedin the NR system.

FIG. 22 schematically illustrates an example in which a symbol lengthfor PTRS and a symbol length for data are set differently from eachother according to some implementations of the present disclosure.

FIG. 23 schematically illustrates an example in which PTRS is deployedaccording to some implementations of the present disclosure.

FIG. 24 schematically illustrates the structure of a receiving end of acommunication device, according to some implementations of the presentdisclosure.

FIG. 25 schematically illustrates another example in which PTRS isdeployed according to some implementations of the present disclosure.

FIG. 26 schematically illustrates an example of an OFDM signalgeneration method according to some implementations of the presentdisclosure.

FIG. 27 schematically illustrates another example of an OFDM signalgeneration method according to some implementations of the presentdisclosure.

FIG. 28 illustrates an example in which a PTRS dedicated resource isdefined according to some implementations of the present disclosure.

FIG. 29 is a flowchart of an example of a method for compensating forphase noise of a UE according to some implementations of the presentdisclosure.

FIG. 30 illustrates a communication system 1 applied to the presentspecification.

FIG. 31 illustrates a wireless device applicable to the presentdisclosure.

FIG. 32 illustrates a signal processing circuit for a transmissionsignal.

FIG. 33 shows another example of a wireless device applied to thepresent disclosure.

FIG. 34 illustrates a portable device applied to the present disclosure.

FIG. 35 illustrates a vehicle or an autonomous driving vehicle appliedto the present disclosure.

FIG. 36 illustrates a vehicle applied to the present disclosure.

FIG. 37 illustrates an XR device applied to the present disclosure.

FIG. 38 illustrates a robot applied to the present disclosure.

FIG. 39 illustrates an AI device applied to the present disclosure.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

In the present specification, “A or B” may mean “only A”, “only B” or“both A and B”. In other words, in the present specification, “A or B”may be interpreted as “A and/or B”. For example, in the presentspecification, “A, B, or C” may mean “only A”, “only B”, “only C”, or“any combination of A, B, C”.

A slash (/) or comma used in the present specification may mean“and/or”. For example, “A/B” may mean “A and/or B”. Accordingly, “A/B”may mean “only A”, “only B”, or “both A and B”. For example, “A, B, C”may mean “A, B, or C”.

In the present specification, “at least one of A and B” may mean “onlyA”, “only B”, or “both A and B”. In addition, in the presentspecification, the expression “at least one of A or B” or “at least oneof A and/or B” may be interpreted as “at least one of A and B”.

In addition, in the present specification, “at least one of A, B, and C”may mean “only A”, “only B”, “only C”, or “any combination of A, B, andC”. In addition, “at least one of A, B, or C” or “at least one of A, B,and/or C” may mean “at least one of A, B, and C”.

In addition, a parenthesis used in the present specification may mean“for example”. Specifically, when indicated as “control information(PDCCH)”, it may mean that “PDCCH” is proposed as an example of the“control information”. In other words, the “control information” of thepresent specification is not limited to “PDCCH”, and “PDCCH” may beproposed as an example of the “control information”. In addition, whenindicated as “control information (i.e., PDCCH)”, it may also mean that“PDCCH” is proposed as an example of the “control information”.

Technical features described individually in one figure in the presentspecification may be individually implemented, or may be simultaneouslyimplemented.

FIG. 1 shows a wireless communication system to which the presentdisclosure may be applied. The wireless communication system may bereferred to as an Evolved-UMTS Terrestrial Radio Access Network(E-UTRAN) or a Long Term Evolution (LTE)/LTE-A system.

The E-UTRAN includes at least one base station (BS) 20 which provides acontrol plane and a user plane to a user equipment (UE) 10. The UE 10may be fixed or mobile, and may be referred to as another terminology,such as a mobile station (MS), a user terminal (UT), a subscriberstation (SS), a mobile terminal (MT), a wireless device, etc. The BS 20is generally a fixed station that communicates with the UE 10 and may bereferred to as another terminology, such as an evolved node-B (eNB), abase transceiver system (BTS), an access point, etc.

The BSs 20 are interconnected by means of an X2 interface. The BSs 20are also connected by means of an S1 interface to an evolved packet core(EPC) 30, more specifically, to a mobility management entity (MME)through S1-MME and to a serving gateway (S-GW) through S1-U.

The EPC 30 includes an MME, an S-GW, and a packet data network-gateway(P-GW). The MME has access information of the UE or capabilityinformation of the UE, and such information is generally used formobility management of the UE. The S-GW is a gateway having an E-UTRANas an end point. The P-GW is a gateway having a PDN as an end point.

Layers of a radio interface protocol between the UE and the network canbe classified into a first layer (L1), a second layer (L2), and a thirdlayer (L3) based on the lower three layers of the open systeminterconnection (OSI) model that is well-known in the communicationsystem. Among them, a physical (PHY) layer belonging to the first layerprovides an information transfer service by using a physical channel,and a radio resource control (RRC) layer belonging to the third layerserves to control a radio resource between the UE and the network. Forthis, the RRC layer exchanges an RRC message between the UE and the BS.

FIG. 2 is a diagram showing a wireless protocol architecture for a userplane. FIG. 3 is a diagram showing a wireless protocol architecture fora control plane. The user plane is a protocol stack for user datatransmission. The control plane is a protocol stack for control signaltransmission.

Referring to FIGS. 2 and 3 , a PHY layer provides an upper layer(=higherlayer) with an information transfer service through a physical channel.The PHY layer is connected to a medium access control (MAC) layer whichis an upper layer of the PHY layer through a transport channel. Data istransferred between the MAC layer and the PHY layer through thetransport channel. The transport channel is classified according to howand with what characteristics data is transferred through a radiointerface.

Data is moved between different PHY layers, that is, the PHY layers of atransmitter and a receiver, through a physical channel. The physicalchannel may be modulated according to an Orthogonal Frequency DivisionMultiplexing (OFDM) scheme, and use the time and frequency as radioresources.

The functions of the MAC layer include mapping between a logical channeland a transport channel and multiplexing and demultiplexing to atransport block that is provided through a physical channel on thetransport channel of a MAC Service Data Unit (SDU) that belongs to alogical channel. The MAC layer provides service to a Radio Link Control(RLC) layer through the logical channel.

The functions of the RLC layer include the concatenation, segmentation,and reassembly of an RLC SDU. In order to guarantee various types ofQuality of Service (QoS) required by a Radio Bearer (RB), the RLC layerprovides three types of operation mode: Transparent Mode (TM),Unacknowledged Mode (UM), and Acknowledged Mode (AM). AM RLC provideserror correction through an Automatic Repeat Request (ARQ).

The RRC layer is defined only on the control plane. The RRC layer isrelated to the configuration, reconfiguration, and release of radiobearers, and is responsible for control of logical channels, transportchannels, and PHY channels. An RB means a logical route that is providedby the first layer (PHY layer) and the second layers (MAC layer, the RLClayer, and the PDCP layer) in order to transfer data between UE and anetwork.

The function of a Packet Data Convergence Protocol (PDCP) layer on theuser plane includes the transfer of user data and header compression andciphering. The function of the PDCP layer on the user plane furtherincludes the transfer and encryption/integrity protection of controlplane data.

What an RB is configured means a process of defining the characteristicsof a wireless protocol layer and channels in order to provide specificservice and configuring each detailed parameter and operating method. AnRB can be divided into two types of a Signaling RB (SRB) and a Data RB(DRB). The SRB is used as a passage through which an RRC message istransmitted on the control plane, and the DRB is used as a passagethrough which user data is transmitted on the user plane.

If RRC connection is established between the RRC layer of UE and the RRClayer of an E-UTRAN, the UE is in the RRC connected state. If not, theUE is in the RRC idle state.

A downlink transport channel through which data is transmitted from anetwork to UE includes a broadcast channel (BCH) through which systeminformation is transmitted and a downlink shared channel (SCH) throughwhich user traffic or control messages are transmitted. Traffic or acontrol message for downlink multicast or broadcast service may betransmitted through the downlink SCH, or may be transmitted through anadditional downlink multicast channel (MCH). Meanwhile, an uplinktransport channel through which data is transmitted from UE to a networkincludes a random access channel (RACH) through which an initial controlmessage is transmitted and an uplink shared channel (SCH) through whichuser traffic or control messages are transmitted.

Logical channels that are placed over the transport channel and that aremapped to the transport channel include a broadcast control channel(BCCH), a paging control channel (PCCH), a common control channel(CCCH), a multicast control channel (MCCH), and a multicast trafficchannel (MTCH).

The physical channel includes several OFDM symbols in the time domainand several subcarriers in the frequency domain. One subframe includes aplurality of OFDM symbols in the time domain. An RB is a resourcesallocation unit, and includes a plurality of OFDM symbols and aplurality of subcarriers. Furthermore, each subframe may use specificsubcarriers of specific OFDM symbols (e.g., the first OFDM symbol) ofthe corresponding subframe for a physical downlink control channel(PDCCH), that is, an L1/L2 control channel. A Transmission Time Interval(TTI) is a unit time of transmission, and may be, for example, asubframe or a slot.

Hereinafter, a new radio access technology (new RAT, NR) will bedescribed.

As more and more communication devices require more communicationcapacity, there is a need for improved mobile broadband communicationover existing radio access technology. Also, massive machine typecommunications (MTC), which provides various services by connecting manydevices and objects, is one of the major issues to be considered in thenext generation communication. In addition, communication system designconsidering reliability/latency sensitive service/UE is being discussed.The introduction of next generation radio access technology consideringenhanced mobile broadband communication (eMBB), massive MTC (mMTC),ultrareliable and low latency communication (URLLC) is discussed. Thisnew technology may be called new radio access technology (new RAT or NR)in the present disclosure for convenience.

FIG. 4 illustrates another example of a wireless communication system towhich technical features of the present disclosure are applicable.

Specifically, FIG. 4 shows system architecture based on a 5G new radioaccess technology (NR) system. Entities used in the 5G NR system(hereinafter, simply referred to as “NR”) may absorb some or allfunctions of the entities (e.g., the eNB, the MME, and the S-GW)introduced in FIG. 1 . The entities used in the NR system may beidentified by terms with “NG” to be distinguished from LTE entities.

Referring to FIG. 4 , the wireless communication system includes atleast one UE 11, a next-generation RAN (NG-RAN), and a 5G core network(5GC). The NG-RAN includes at least one NG-RAN node. The NG-RAN node isan entity corresponding to the BS 20 illustrated in FIG. 5 . The NG-RANnode includes at least one gNB 21 and/or at least one ng-eNB 22. The gNB21 provides an end point of NR control-plane and user-plane protocols tothe UE 11. The ng-eNB 22 provides an end point of E-UTRA user-plane andcontrol-plane protocols to the UE 11.

The 5GC includes an access and mobility management function (AMF), auser plane function (UPF), and a session management function (SMF). TheAMF hosts functions of NAS security and idle-state mobility processing.The AMF is an entity that includes the functions of a conventional MME.The UPF hosts functions of mobility anchoring function and protocol dataunit (PDU) processing. The UPF is an entity that includes the functionsof a conventional S-GW. The SMF hosts functions of UE IP addressallocation and PDU session control.

The gNB and the ng-eNB are connected to each other via an Xn interface.The gNB and the ng-eNB are also connected to the 5GC through an NGinterface. Specifically, the gNB and the ng-eNB are connected to the AMFthrough an NG-C interface, and to the UPF through an NG-U interface.

FIG. 5 illustrates a functional division between an NG-RAN and a 5GC.

Referring to FIG. 5 , the gNB may provide functions such as aninter-cell radio resource management (Inter Cell RRM), radio bearermanagement (RB control), connection mobility control, radio admissioncontrol, measurement configuration & provision, dynamic resourceallocation, and the like. The AMF may provide functions such as NASsecurity, idle state mobility handling, and so on. The UPF may providefunctions such as mobility anchoring, PDU processing, and the like. TheSMF may provide functions such as UE IP address assignment, PDU sessioncontrol, and so on.

FIG. 6 illustrates an example of a frame structure that may be appliedin NR.

Referring to FIG. 6 , a frame may be configured in 10 milliseconds (ms),and may include 10 subframes configured in 1 ms.

In NR, uplink and downlink transmission may be composed of frames. Aradio frame has a length of 10 ms and may be defined as two 5 mshalf-frames (HF). The HF may be defined as five 1 ms subframes (SFs).The SF may be divided into one or more slots, and the number of slotswithin the SF depends on a subcarrier spacing (SCS). Each slot includes12 or 14 OFDM(A) symbols according to a cyclic prefix (CP). In case ofusing a normal CP, each slot includes 14 symbols. In case of using anextended CP, each slot includes 12 symbols. Herein, a symbol may includean OFDM symbol (or CP-OFDM symbol) and a Single Carrier-FDMA (SC-FDMA)symbol (or Discrete Fourier Transform-spread-OFDM (DFT-s-OFDM) symbol).

One or a plurality of slots may be included in the subframe according tosubcarrier spacing.

The following table 1 illustrates a subcarrier spacing configuration μ.

TABLE 1 μ Δf = 2^(μ) · 15[kHz] Cyclic prefix 0 15 Normal 1 30 Normal 260 Normal Extended 3 120 Normal 4 240 Normal

The following table 2 illustrates the number of slots in a frame(N^(frame,μ) _(slot)), the number of slots in a subframe (N^(subframe,μ)_(slot)), the number of symbols in a slot (N^(slot) _(symb)), and thelike, according to subcarrier spacing configurations μ.

TABLE 2 μ N_(symb) ^(slot) N_(slot) ^(frame, μ) N_(slot) ^(subframe, μ)0 14 10 1 1 14 20 2 2 14 40 4 3 14 80 8 4 14 160 16

Table 3 illustrates that the number of symbols per slot, the number ofslots per frame, and the number of slots per subframe vary depending onthe SCS, in case of using an extended CP.

TABLE 3 SCS (15 · 2^(μ)) N^(slot) _(symb) N^(frame, u) _(slot)N^(subframe, u) _(slot) 60 kHz (μ = 2) 12 40 4

In an NR system, OFDM(A) numerologies (e.g., SCS, CP length, and so on)may be differently configured between a plurality of cells integrated toone UE. Accordingly, an (absolute time) duration of a time resource(e.g., SF, slot or TTI) (for convenience, collectively referred to as atime unit (TU)) configured of the same number of symbols may bedifferently configured between the integrated cells.

FIG. 7 illustrates a slot structure.

Referring to FIG. 7 , a slot may include a plurality of symbols in atime domain. For example, in case of a normal CP, one slot may include14 symbols. However, in case of an extended CP, one slot may include 12symbols. Or, in case of a normal CP, one slot may include 7 symbols.However, in case of an extended CP, one slot may include 6 symbols.

A carrier may include a plurality of subcarriers in a frequency domain.A resource block (RB) may be defined as a plurality of consecutivesubcarriers (e.g., 12 subcarriers) in the frequency domain. A bandwidthpart (BWP) may be defined as a plurality of consecutive (physical)resource blocks ((P)RBs) in the frequency domain, and the BWP maycorrespond to one numerology (e.g., SCS, CP length, and so on). Thecarrier may include up to N (e.g., 5) BWPs. Data communication may beperformed via an activated BWP. In a resource grid, each element may bereferred to as a resource element (RE), and one complex symbol may bemapped thereto.

A physical downlink control channel (PDCCH) may include one or morecontrol channel elements (CCEs) as illustrated in the following table 4.

TABLE 4 Aggregation level Number of CCEs 1 1 2 2 4 4 8 8 16 16

That is, the PDCCH may be transmitted through a resource including 1, 2,4, 8, or 16 CCEs. Here, the CCE includes six resource element groups(REGs), and one REG includes one resource block in a frequency domainand one orthogonal frequency division multiplexing (OFDM) symbol in atime domain.

Meanwhile, a new unit called a control resource set (CORESET) may beintroduced in the NR. The UE may receive a PDCCH in the CORESET.

FIG. 8 illustrates CORESET.

Referring to FIG. 8 , the CORESET includes N^(CORESET) _(RB) number ofresource blocks in the frequency domain, and N^(CORESET) _(symb) ∈ {1,2, 3} number of symbols in the time domain. N^(CORESET) _(RB) andN^(CORESET) _(symb) may be provided by a base station via higher layersignaling. As illustrated in FIG. 8 , a plurality of CCEs (or REGs) maybe included in the CORESET.

The UE may attempt to detect a PDCCH in units of 1, 2, 4, 8, or 16 CCEsin the CORESET. One or a plurality of CCEs in which PDCCH detection maybe attempted may be referred to as PDCCH candidates.

A plurality of CORESETs may be configured for the UE.

FIG. 9 is a diagram illustrating a difference between a related artcontrol region and the CORESET in NR.

Referring to FIG. 9 , a control region 300 in the related art wirelesscommunication system (e.g., LTE/LTE-A) is configured over the entiresystem band used by a base station (BS). All the UEs, excluding some(e.g., eMTC/NB-IoT UE) supporting only a narrow band, shall be able toreceive wireless signals of the entire system band of the BS in order toproperly receive/decode control information transmitted by the BS.

On the other hand, in NR, CORESET described above was introduced.CORESETs 301, 302, and 303 are radio resources for control informationto be received by the UE and may use only a portion, rather than theentirety of the system bandwidth. The BS may allocate the CORESET toeach UE and may transmit control information through the allocatedCORESET. For example, in FIG. 9 , a first CORESET 301 may be allocatedto UE 1, a second CORESET 302 may be allocated to UE 2, and a thirdCORESET 303 may be allocated to UE 3. In the NR, the UE may receivecontrol information from the BS, without necessarily receiving theentire system band.

The CORESET may include a UE-specific CORESET for transmittingUE-specific control information and a common CORESET for transmittingcontrol information common to all UEs.

Meanwhile, NR may require high reliability according to applications. Insuch a situation, a target block error rate (BLER) for downlink controlinformation (DCI) transmitted through a downlink control channel (e.g.,physical downlink control channel (PDCCH)) may remarkably decreasecompared to those of conventional technologies. As an example of amethod for satisfying requirement that requires high reliability,content included in DCI can be reduced and/or the amount of resourcesused for DCI transmission can be increased. Here, resources can includeat least one of resources in the time domain, resources in the frequencydomain, resources in the code domain and resources in the spatialdomain.

Meanwhile, in NR, the following technologies/features can be applied.

<Self-Contained Subframe Structure>

FIG. 10 illustrates an example of a frame structure for new radio accesstechnology.

In NR, a structure in which a control channel and a data channel aretime-division-multiplexed within one TTI, as shown in FIG. 10 , can beconsidered as a frame structure in order to minimize latency.

In FIG. 10 , a shaded region represents a downlink control region and ablack region represents an uplink control region. The remaining regionmay be used for downlink (DL) data transmission or uplink (UL) datatransmission. This structure is characterized in that DL transmissionand UL transmission are sequentially performed within one subframe andthus DL data can be transmitted and UL ACK/NACK can be received withinthe subframe. Consequently, a time required from occurrence of a datatransmission error to data retransmission is reduced, thereby minimizinglatency in final data transmission.

In this data and control TDMed subframe structure, a time gap for a basestation and a UE to switch from a transmission mode to a reception modeor from the reception mode to the transmission mode may be required. Tothis end, some OFDM symbols at a time when DL switches to UL may be setto a guard period (GP) in the self-contained subframe structure.

FIG. 11 illustrates a structure of a self-contained slot.

Referring to FIG. 11 , one slot may have a self-contained structure inwhich all of a DL control channel, DL or UL data, and a UL controlchannel may be included. For example, first N symbols (hereinafter, DLcontrol region) in the slot may be used to transmit a DL controlchannel, and last M symbols (hereinafter, UL control region) in the slotmay be used to transmit a UL control channel. N and M are integersgreater than or equal to 0. A resource region (hereinafter, a dataregion) which exists between the DL control region and the UL controlregion may be used for DL data transmission or UL data transmission. Forexample, the following configuration may be considered. Respectivedurations are listed in a temporal order.

1. DL only configuration

2. UL only configuration

3. Mixed UL-DL configuration

-   -   DL region+Guard period (GP)+UL control region    -   DL control region+GP+UL region

Here, the DL region may be (i) DL data region, (ii) DL control region+DLdata region. The UL region may be (i) UL data region, (ii) UL dataregion+UL control region

A PDCCH may be transmitted in the DL control region, and a physicaldownlink shared channel (PDSCH) may be transmitted in the DL dataregion. A physical uplink control channel (PUCCH) may be transmitted inthe UL control region, and a physical uplink shared channel (PUSCH) maybe transmitted in the UL data region. Downlink control information(DCI), for example, DL data scheduling information, UL data schedulinginformation, and the like, may be transmitted on the PDCCH. Uplinkcontrol information (UCI), for example, ACK/NACK information about DLdata, channel state information (CSI), and a scheduling request (SR),may be transmitted on the PUCCH. A GP provides a time gap in a processin which a BS and a UE switch from a TX mode to an RX mode or a processin which the BS and the UE switch from the RX mode to the TX mode. Somesymbols at the time of switching from DL to UL within a subframe may beconfigured as the GP.

<Analog Beamforming #1>

Wavelengths are shortened in millimeter wave (mmW) and thus a largenumber of antenna elements can be installed in the same area. That is,the wavelength is 1 cm at 30 GHz and thus a total of 100 antennaelements can be installed in the form of a 2-dimensional array at aninterval of 0.5 lambda (wavelength) in a panel of 5×5 cm. Accordingly,it is possible to increase a beamforming (BF) gain using a large numberof antenna elements to increase coverage or improve throughput in mmW.

In this case, if a transceiver unit (TXRU) is provided to adjusttransmission power and phase per antenna element, independentbeamforming per frequency resource can be performed. However,installation of TXRUs for all of about 100 antenna elements decreaseseffectiveness in terms of cost. Accordingly, a method of mapping a largenumber of antenna elements to one TXRU and controlling a beam directionusing an analog phase shifter is considered. Such analog beamforming canform only one beam direction in all bands and thus cannot providefrequency selective beamforming.

Hybrid beamforming (BF) having a number B of TXRUs which is smaller thanQ antenna elements can be considered as an intermediate form of digitalBF and analog BF. In this case, the number of directions of beams whichcan be simultaneously transmitted are limited to B although it dependson a method of connecting the B TXRUs and the Q antenna elements.

<Analog Beamforming #2>

When a plurality of antennas is used in NR, hybrid beamforming which isa combination of digital beamforming and analog beamforming is emerging.Here, in analog beamforming (or RF beamforming) an RF end performsprecoding (or combining) and thus it is possible to achieve theperformance similar to digital beamforming while reducing the number ofRF chains and the number of D/A (or A/D) converters. For convenience,the hybrid beamforming structure may be represented by N TXRUs and Mphysical antennas. Then, the digital beamforming for the L data layersto be transmitted at the transmitting end may be represented by an N byL matrix, and the converted N digital signals are converted into analogsignals via TXRUs, and analog beamforming represented by an M by Nmatrix is applied.

FIG. 12 is an abstract diagram of a hybrid beamforming structure fromthe viewpoint of the TXRU and the physical antenna.

In FIG. 12 , the number of digital beams is L, and the number of analogbeams is N. Furthermore, in the NR system, a direction of supportingmore efficient beamforming to a UE located in a specific area isconsidered by designing the base station to change analog beamforming inunits of symbols. Further, when defining N specific TXRUs and M RFantennas as one antenna panel in FIG. 12 , in the NR system, a method ofintroducing a plurality of antenna panels to which hybrid beamformingindependent of each other can be applied is being considered.

As described above, when the base station uses a plurality of analogbeams, since analog beams advantageous for signal reception may bedifferent for each UE, a beam sweeping operation, in which at least fora synchronization signal, system information, paging, etc., a pluralityof analog beams to be applied by the base station in a specific subframeare changed for each symbol, that allows all UEs to have a receptionoccasion is being considered.

FIG. 13 shows a synchronization signal and a PBCH (SS/PBCH) block.

Referring to FIG. 13 , an SS/PBCH block may include a PSS and an SSS,each of which occupies one symbol and 127 subcarriers, and a PBCH, whichspans three OFDM symbols and 240 subcarriers where one symbol mayinclude an unoccupied portion in the middle reserved for the SSS. Theperiodicity of the SS/PBCH block may be configured by a network, and atime position for transmitting the SS/PBCH block may be determined onthe basis of subcarrier spacing.

Polar coding may be used for the PBCH. A UE may assume band-specificsubcarrier spacing for the SS/PBCH block as long as a network does notconfigure the UE to assume different subcarrier spacings.

The PBCH symbols carry frequency-multiplexed DMRS thereof. QPSK may beused for the PBCH. 1008 unique physical-layer cell IDs may be assigned.

For a half frame with SS/PBCH blocks, first symbol indices for candidateSS/PBCH blocks are determined according to subcarrier spacing of SS/PBCHblocks, which will be described later.

-   -   Case A—Subcarrier spacing 15 kHz: The first symbols of the        candidate SS/PBCH blocks have an index of {2, 8}+14*n. For        carrier frequencies less than or equal to 3 GHz, n=0, 1. For        carrier frequencies greater than 3 GHz and less than or equal to        6 GHz, n=0, 1, 2, 3.    -   Case B—Subcarrier spacing 30 kHz: The first symbols of the        candidate SS/PBCH blocks have an index of {4, 8, 16, 20}+28*n.        For carrier frequencies less than or equal to 3 GHz, n=0. For        carrier frequencies greater than 3 GHz and less than or equal to        6 GHz, n=0, 1.    -   Case C—Subcarrier spacing 30 kHz: The first symbols of candidate        SS/PBCH blocks have an index of {2, 8}+14*n. For carrier        frequencies less than or equal to 3 GHz, n=0, 1. For carrier        frequencies greater than 3 GHz and less than or equal to 6 GHz,        n=0, 1, 2, 3.    -   Case D—Subcarrier spacing 120 kHz: The first symbols of the        candidate SS/PBCH blocks have an index of {4, 8, 16, 20}+28*n.        For carrier frequencies greater than 6 GHz, n=0, 1, 2, 3, 5, 6,        7, 8, 10, 11, 12, 13, 15, 16, 17, 18.    -   Case E—Subcarrier spacing 240 kHz: The first symbols of the        candidate SS/PBCH blocks have an index of {8, 12, 16, 20, 32,        36, 40, 44}+56*n. For carrier frequencies greater than 6 GHz,        n=0, 1, 2, 3, 5, 6, 7, 8.

Candidate SS/PBCH blocks in a half frame are indexed in ascending orderfrom 0 to L−1 on the time axis. The UE shall determine 2 LSB bits forL=4 and 3 LSB bits for L>4 of the SS/PBCH block index per half framefrom one-to-one mapping with the index of the DMRS sequence transmittedin the PBCH. For L=64, the UE shall determine 3 MSB bits of the SS/PBCHblock index per half frame by the PBCH payload bits.

By the higher layer parameter ‘SSB-transmitted-SIB1’, the index ofSS/PBCH blocks in which the UE cannot receive other signals or channelsin REs overlapping with REs corresponding to SS/PBCH blocks can be set.In addition, according to the higher layer parameter ‘SSB-transmitted’,the index of SS/PBCH blocks per serving cell in which the UE cannotreceive other signals or channels in REs overlapping with REscorresponding to the SS/PBCH blocks can be set. The setting by‘SSB-transmitted’ may take precedence over the setting by‘SSB-transmitted-SIB1’. A periodicity of a half frame for reception ofSS/PBCH blocks per serving cell may be set by a higher layer parameter‘SSB-periodicityServingCell’. If the UE does not set the periodicity ofthe half frame for the reception of SS/PBCH blocks, the UE shall assumethe periodicity of the half frame. The UE may assume that theperiodicity is the same for all SS/PBCH blocks in the serving cell.

FIG. 14 is for explaining a method for a UE to obtain timinginformation.

First, the UE may obtain 6-bit SFN information through the MIB (MasterInformation Block) received in the PBCH. In addition, SFN 4 bits can beobtained in the PBCH transport block.

Second, the UE may obtain a 1-bit half frame indicator as part of thePBCH payload. In less than 3 GHz, the half frame indicator may beimplicitly signaled as part of the PBCH DMRS for Lmax=4.

Finally, the UE may obtain the SS/PBCH block index by the DMRS sequenceand the PBCH payload. That is, LSB 3 bits of the SS block index can beobtained by the DMRS sequence for a period of 5 ms. Also, the MSB 3 bitsof the timing information are explicitly carried within the PBCH payload(for >6 GHz).

In initial cell selection, the UE may assume that a half frame withSS/PBCH blocks occurs with a periodicity of 2 frames. Upon detecting theSS/PBCH block, the UE determines that a control resource set for theType0-PDCCH common search space exists if k_(SSB)≤23 for FR1 andk_(SSB)≤11 for FR2. The UE determines that there is no control resourceset for the Type0-PDCCH common search space if k_(SSB)>23 for FR1 andk_(SSB)>11 for FR2.

For a serving cell without transmission of SS/PBCH blocks, the UEacquires time and frequency synchronization of the serving cell based onreception of the SS/PBCH blocks on the PSCell or the primary cell of thecell group for the serving cell.

Hereinafter, system information acquisition will be described.

System information (SI) is divided into a master information block (MIB)and a plurality of system information blocks (SIBs) where:

-   -   the MIB is transmitted always on a BCH according to a period of        40 ms, is repeated within 80 ms, and includes parameters        necessary to obtain system information block type1 (SIB1) from a        cell;    -   SIB1 is periodically and repeatedly transmitted on a DL-SCH.        SIB1 includes information on availability and scheduling (e.g.,        periodicity or SI window size) of other SIBs. Further, SIB1        indicates whether the SIBs (i.e., the other SIBs) are        periodically broadcast or are provided by request. When the        other SIBs are provided by request, SIB1 includes information        for a UE to request SI;    -   SIBs other than SIB1 are carried via system information (SI)        messages transmitted on the DL-SCH. Each SI message is        transmitted within a time-domain window (referred to as an SI        window) periodically occurring;    -   For a PSCell and SCells, an RAN provides required SI by        dedicated signaling. Nevertheless, a UE needs to acquire an MIB        of the PSCell in order to obtain the SFN timing of a SCH (which        may be different from an MCG). When relevant SI for a SCell is        changed, the RAN releases and adds the related SCell. For the        PSCell, SI can be changed only by reconfiguration with        synchronization (sync).

FIG. 15 shows an example of a process of acquiring system information ofa UE.

According to FIG. 15 , the UE may receive the MIB from the network andthen receive the SIB1. Thereafter, the UE may transmit a systeminformation request to the network, and may receive a ‘SystemInformationmessage’ from the network in response thereto.

The UE may apply a system information acquisition procedure foracquiring AS (access stratum) and NAS (non-access stratum) information.

UEs in RRC_IDLE and RRC_INACTIVE states shall ensure (at least) validversions of MIB, SIB1 and SystemInformationBlockTypeX (according to therelevant RAT support for UE-controlled mobility).

The UE in RRC_CONNECTED state shall guarantee valid versions of MIB,SIB1, and SystemInformationBlockTypeX (according to mobility support forthe related RAT).

The UE shall store the related SI obtained from the currentlycamped/serving cell. The SI version obtained and stored by the UE isvalid only for a certain period of time. The UE may use this storedversion of the SI after, for example, cell reselection, return from outof coverage, or system information change indication.

Hereinafter, random access will be described.

The random access procedure of the UE can be summarized as in thefollowing table 5.

TABLE 5 Type of signal Action/Acquired Information Step 1 Uplink PRACHInitial beam acquisition preamble Random Election of RA-Preamble ID Step2 Random access Timing arrangement response on DL-SCH informationRA-preamble ID Initial uplink grant, temporary C-RNTI Step 3 Uplinktransmission RRC connection request on UL-SCH UE identifier Step 4Contention resolution C-RNTI on PDCCH of downlink for initial accessC-RNTI on PDCCH for UE in RRC_CONNECTED state

FIG. 16 is for explaining a random access procedure.

Referring to FIG. 16 , first, the UE may transmit a physical randomaccess channel (PRACH) preamble in uplink as message (Msg) 1 of therandom access procedure.

Random access preamble sequences having two different lengths aresupported. A long sequence of length 839 applies to subcarrier spacingsof 1.25 kHz and 5 kHz, and a short sequence of length 139 applies tosubcarrier spacings of 15, 30, 60, and 120 kHz. A long sequence supportsan unrestricted set and a limited set of types A and B, whereas a shortsequence supports only an unrestricted set.

A plurality of RACH preamble formats are defined with one or more RACHOFDM symbols, a different cyclic prefix (CP), and a guard time. ThePRACH preamble configuration to be used is provided to the UE as systeminformation.

If there is no response to Msg1, the UE may retransmit the power-rammedPRACH preamble within a prescribed number of times. The UE calculatesthe PRACH transmission power for retransmission of the preamble based onthe most recent estimated path loss and power ramping counter. If the UEperforms beam switching, the power ramping counter does not change.

FIG. 17 is a diagram for describing a power ramping counter.

The UE may perform power ramping for retransmission of the random accesspreamble based on the power ramping counter. Here, as described above,the power ramping counter does not change when the UE performs beamswitching during PRACH retransmission.

Referring to FIG. 17 , when the UE retransmits the random accesspreamble for the same beam, the UE increments the power ramping counterby 1 as the power ramping counter increases from 1 to 2 and from 3 to 4.However, when the beam is changed, the power ramping counter does notchange during PRACH retransmission.

FIG. 18 is for explaining the concept of the threshold value of the SSblock for the RACH resource relationship.

The system information informs the UE of the relationship between SSblocks and RACH resources. The threshold of the SS block for the RACHresource relationship is based on RSRP and network configuration.Transmission or retransmission of the RACH preamble is based on an SSblock that satisfies a threshold. Accordingly, in the example of FIG. 18, since the SS block m exceeds the threshold of the received power, theRACH preamble is transmitted or retransmitted based on the SS block m.

Thereafter, when the UE receives a random access response on the DL-SCH,the DL-SCH may provide timing arrangement information, an RA-preambleID, an initial uplink grant, and a temporary C-RNTI.

Based on the information, the UE may perform uplink transmission on theUL-SCH as Msg3 of the random access procedure. Msg3 may include the RRCconnection request and UE identifier.

In response, the network may transmit Msg4, which may be treated as acontention resolution message, in downlink. By receiving this, the UEcan enter the RRC connected state.

<Bandwidth Part (BWP)>

In the NR system, a maximum of 400 MHz can be supported per componentcarrier (CC). If a UE operating in such a wideband CC operates with RFfor all CCs turn on all the time, UE battery consumption may increase.Or, considering use cases operating in one wideband CC (e.g., eMBB,URLLC, mMTC, etc.), different numerologies (e.g., subcarrier spacings(SCSs)) can be supported for different frequency bands in the CC. Or,UEs may have different capabilities for a maximum bandwidth. Inconsideration of this, an eNB may instruct a UE to operate only in apart of the entire bandwidth of a wideband CC, and the part of thebandwidth is defined as a bandwidth part (BWP) for convenience. A BWPcan be composed of resource blocks (RBs) consecutive on the frequencyaxis and can correspond to one numerology (e.g., a subcarrier spacing, acyclic prefix (CP) length, a slot/mini-slot duration, or the like).

Meanwhile, the eNB can configure a plurality of BWPs for a UE evenwithin one CC. For example, a BWP occupying a relatively small frequencyregion can be set in a PDCCH monitoring slot and a PDSCH indicated by aPDCCH can be scheduled on a BWP wider than the BWP. When UEs converge ona specific BWP, some UEs may be set to other BWPs for load balancing.Otherwise, BWPs on both sides of a bandwidth other than some spectra atthe center of the bandwidth may be configured in the same slot inconsideration of frequency domain inter-cell interference cancellationbetween neighbor cells. That is, the eNB can configure at least oneDL/UL BWP for a UE associated with(=related with) a wideband CC andactivate at least one of DL/UL BWPs configured at a specific time(through L1 signaling or MAC CE or RRC signaling), and switching toother configured DL/UL BWPs may be indicated (through L1 signaling orMAC CE or RRC signaling) or switching to a determined DL/UL BWP mayoccur when a timer value expires on the basis of a timer. Here, anactivated DL/UL BWP is defined as an active DL/UL BWP. However, a UE maynot receive a configuration for a DL/UL BWP when the UE is in an initialaccess procedure or RRC connection is not set up. In such a situation, aDL/UL BWP assumed by the UE is defined as an initial active DL/UL BWP.

<DRX (Discontinuous Reception)>

Discontinuous Reception (DRX) refers to an operation mode in which a UE(User Equipment) reduces battery consumption so that the UE candiscontinuously receive a downlink channel That is, the UE configuredfor DRX can reduce power consumption by discontinuously receiving the DLsignal.

The DRX operation is performed within a DRX cycle indicating a timeinterval in which On Duration is periodically repeated. The DRX cycleincludes an on-duration and a sleep duration (or a DRX opportunity). Theon-duration indicates a time interval during which the UE monitors thePDCCH to receive the PDCCH.

DRX may be performed in RRC (Radio Resource Control)_IDLE state (ormode), RRC_INACTIVE state (or mode), or RRC_CONNECTED state (or mode).In RRC_IDLE state and RRC_INACTIVE state, DRX may be used to receivepaging signal discontinuously.

-   -   RRC_IDLE state: a state in which a radio connection (RRC        connection) is not established between the base station and the        UE.    -   RRC_INACTIVE state: A wireless connection (RRC connection) is        established between the base station and the UE, but the        wireless connection is inactive.    -   RRC_CONNECTED state: a state in which a radio connection (RRC        connection) is established between the base station and the UE.

DRX can be basically divided into idle mode DRX, connected DRX (C-DRX),and extended DRX.

DRX applied in the IDLE state may be named idle mode DRX, and DRXapplied in the CONNECTED state may be named connected mode DRX (C-DRX).

Extended/Enhanced DRX (eDRX) is a mechanism that can extend the cyclesof idle mode DRX and C-DRX, and Extended/Enhanced DRX (eDRX) can bemainly used for (massive) IoT applications. In idle mode DRX, whether toallow eDRX may be configured based on system information (e.g., SIB1).SIB1 may include an eDRX-allowed parameter. The eDRX-allowed parameteris a parameter indicating whether idle mode extended DRX is allowed.

<Idle Mode DRX>

In the idle mode, the UE may use DRX to reduce power consumption. Onepaging occasion (paging occasion; PO) is a subframe in which P-RNTI(Paging-Radio Network Temporary Identifier) can be transmitted throughPDCCH (Physical Downlink Control Channel), MPDCCH (MTC PDCCH), or NPDCCH(a narrowband PDCCH) (which addresses the paging message for NB-IoT).

In P-RNTI transmitted through MPDCCH, PO may indicate a start subframeof MPDCCH repetition. In the case of the P-RNTI transmitted through theNPDCCH, when the subframe determined by the PO is not a valid NB-IoTdownlink subframe, the PO may indicate the start subframe of the NPDCCHrepetition. Therefore, the first valid NB-IoT downlink subframe after POis the start subframe of NPDCCH repetition.

One paging frame (PF) is one radio frame that may include one or aplurality of paging occasions. When DRX is used, the UE only needs tomonitor one PO per DRX cycle. One paging narrow band (PNB) is one narrowband in which the UE performs paging message reception. PF, PO, and PNBmay be determined based on DRX parameters provided in systeminformation.

FIG. 19 is a flowchart illustrating an example of performing an idlemode DRX operation.

According to FIG. 19 , the UE may receive idle mode DRX configurationinformation from the base station through higher layer signaling (e.g.,system information) (S21).

The UE may determine a Paging Frame (PF) and a Paging Occasion (PO) tomonitor the PDCCH in the paging DRX cycle based on the idle mode DRXconfiguration information (S22). In this case, the DRX cycle may includean on-duration and a sleep duration (or an opportunity of DRX).

The UE may monitor the PDCCH in the PO of the determined PF (S23). Here,for example, the UE monitors only one subframe (PO) per paging DRXcycle. In addition, when the UE receives the PDCCH scrambled by theP-RNTI during the on-duration (i.e., when paging is detected), the UEmay transition to the connected mode and may transmit/receive datato/from the base station.

<Connected Mode DRX(C-DRX)>

C-DRX means DRX applied in the RRC connection state. The DRX cycle ofC-DRX may consist of a short DRX cycle and/or a long DRX cycle. Here, ashort DRX cycle may correspond to an option.

When C-DRX is configured, the UE may perform PDCCH monitoring for theon-duration. If the PDCCH is successfully detected during PDCCHmonitoring, the UE may operate (or run) an inactive timer and maintainan awake state. Conversely, if the PDCCH is not successfully detectedduring PDCCH monitoring, the UE may enter the sleep state after theon-duration ends.

When C-DRX is configured, a PDCCH reception occasion (e.g., a slothaving a PDCCH search space) may be configured non-contiguously based onthe C-DRX configuration. In contrast, if C-DRX is not configured, aPDCCH reception occasion (e.g., a slot having a PDCCH search space) maybe continuously configured in the present disclosure.

On the other hand, PDCCH monitoring may be limited to a time intervalset as a measurement gap (gap) regardless of the C-DRX configuration.

FIG. 20 illustrates a DRX cycle.

Referring to FIG. 20 , a DRX cycle includes “On Duration” and“Opportunity for DRX”. The DRX cycle defines a time interval in which“On Duration” is periodically repeated. “On Duration” represents a timeperiod that the UE monitors to receive the PDCCH. When DRX isconfigured, the UE performs PDCCH monitoring during “On Duration”. Ifthere is a PDCCH successfully detected during PDCCH monitoring, the UEoperates an inactivity timer and maintains an awake state. Meanwhile, ifthere is no PDCCH successfully detected during PDCCH monitoring, the UEenters a sleep state after the “On Duration” is over. Accordingly, whenDRX is configured, PDCCH monitoring/reception may be discontinuouslyperformed in the time domain in performing the procedures and/or methodsdescribed/suggested above. For example, when DRX is configured, in thepresent disclosure, a PDCCH reception occasion (e.g., a slot having aPDCCH search space) may be set discontinuously according to the DRXconfiguration. Meanwhile, when DRX is not configured, PDCCHmonitoring/reception may be continuously performed in the time domain inperforming the procedure and/or method described/proposed above. Forexample, when DRX is not configured, a PDCCH reception occasion (e.g., aslot having a PDCCH search space) may be continuously set in the presentdisclosure. Meanwhile, regardless of DRX configuration, PDCCH monitoringmay be restricted in a time period set as a measurement gap.

Table 6 shows a UE procedure related to the DRX (RRC_CONNECTED state).Referring to Table 6, DRX configuration information is received throughhigher layer (e.g., RRC) signaling, and DRX ON/OFF is controlled by aDRX command of the MAC layer. When DRX is configured, the UE maydiscontinuously perform PDCCH monitoring in performing the procedureand/or method described/proposed in the present disclosure.

TABLE 6 Type of signals UE procedure 1^(st) step RRC signallingReception of DRX configuration (MAC- information CellGroupConfig) 2^(nd)Step MACCE Reception of DRX command ((Long) DRX command MAC CE) 3^(rd)Step — Monitor a PDCCH during an ‘on-duration’ of a DRX cycle)

MAC-CellGroupConfig may include configuration information required toset a medium access control (MAC) parameter for a cell group.MAC-CellGroupConfig may also include configuration information on DRX.For example, MAC-CellGroupConfig may include information as follows indefining DRX.

-   -   Value of drx-OnDurationTimer: It defines a length of a start        interval of a DRX cycle.    -   Value of drx-InactivityTimer: It defines a length of a time        interval in which the UE is awake after a PDCCH occasion in        which the PDCCH indicating initial UL or DL data is detected    -   Value of drx-HARQ-RTT-TimerDL: It defines a length of a maximum        time interval until DL retransmission is received, after initial        DL transmission is received.    -   Value of drx-HARQ-RTT-TimerUL: It defines a length of a maximum        time interval until a grant for UL retransmission is received,        after a grant for UL initial transmission is received.    -   drx-LongCycleStartOffset: It defines a time length and a start        point of a DRX cycle    -   drx-ShortCycle (optional): It defines a time length of a short        DRX cycle

Here, if any one of drx-OnDurationTimer, drx-InactivityTimer,drx-HARQ-RTT-TimerDL, drx-HARQ-RTT-TimerUL is in operation, the UEperforms PDCCH monitoring at every PDCCH occasion while maintaining anawake state.

Hereinafter, the proposal of the present disclosure will be described inmore detail.

The following drawings were created to explain a specific example of thepresent specification. Since the names of specific devices or the namesof specific signals/messages/fields described in the drawings arepresented by way of example, the technical features of the presentspecification are not limited to the specific names used in thefollowing drawings.

First, the effect of phase noise will be described.

The transmitting end performs modulation using a phase locked loop (PLL)to generate a transmission signal in the corresponding band, and thereceiving end also converts the transmitted signal to a baseband usingthe PLL. At this time, if a high frequency band such as terahertz (THz)is used, the PLL must generate an oscillation frequency suitable for thecorresponding frequency. In this case, when a high frequency isgenerated, a lot of phase noise is generated. Here, the power spectraldensity (PSD) of the phase noise generated in the PLL may be expressedas follows.

$\begin{matrix}{{S(f)} = {{{PSD}0{\prod\limits_{n = 1}^{N}\frac{1 + ( \frac{f}{f_{z,n}} )^{2}}{1 + ( \frac{f}{f_{p,n}} )^{2}}}} + {20{\log_{10}( {f_{c}/f_{c,{base}}} )}}}} & \lbrack {{Equation}1} \rbrack\end{matrix}$

That is, the PSD of the phase noise at the reference frequency generatedby the PLL is generated as high as 20 log(f_(e)/f_(e,base)) byincreasing the frequency band. Here, f_(z,n) denotes a zero frequency,f_(p,n) denotes a pole frequency, and PSD0 denotes a power spectrumdensity when the frequency is 0, respectively. Such phase noise affectsthe received signal in a form of causing performance degradation in thetransmission/reception process.

Equation 2 represents a baseband received signal sampled in the digitaldomain when only the phase noise of the receiving end is considered.

$\begin{matrix}{{y\lbrack n\rbrack} = {{\frac{1}{\sqrt{N}}{\sum\limits_{k = 0}^{N - 1}{S_{k}e^{j\frac{2\pi}{N}{kn}}e^{j{\theta\lbrack n\rbrack}}}}} + {n^{\prime}\lbrack n\rbrack}}} & \lbrack {{Equation}2} \rbrack\end{matrix}$

Here, n′[n] denotes a signal including phase noise in additive whiteGaussian noise (AWGN), and θ[n] denotes a phase noise in the n^(th)sample, respectively. That is, Equation 2 represents a signal in which asignal including a phase noise is added to AWGN to a signal obtained bymultiplying a transmission signal by a noisy carrier exp(jθ[n]).

Here, when the signal on the m-th subcarrier is analyzed, Equation 3 isobtained.

$\begin{matrix}{{\hat{S}}_{m} = {{{\frac{1}{N}{\sum\limits_{n = 0}^{N - 1}{{y\lbrack n\rbrack}e^{{- j}\frac{2\pi}{N}{mn}}}}} + N_{m}} = {{S_{m}\frac{1}{N}{\sum\limits_{n = 0}^{N - 1}e^{j{\theta\lbrack n\rbrack}}}} + {\frac{1}{N}{\sum\limits_{{k = 0},{k \neq m}}^{N - 1}{S_{k}{\sum\limits_{n = 0}^{N - 1}{e^{j\frac{2\pi n}{N}{({k - m})}}e^{j{\theta\lbrack n\rbrack}}}}}}} + N_{m}}}} & \lbrack {{Equation}3} \rbrack\end{matrix}$

In Equation 3,

$S_{m}\frac{1}{N}{\sum_{n = 0}^{N - 1}e^{j{\theta\lbrack n\rbrack}}}$

is the common phase noise,

$\frac{1}{N}{\sum_{{k = 0},{k \neq m}}^{N - 1}{S_{k}{\sum_{n = 0}^{N - 1}{e^{j\frac{2\pi n}{N}{({k - m})}}e^{j{\theta\lbrack n\rbrack}}}}}}$

is cross-carrier interference (ICI) due to phase noise, respectively.

On the other hand, as a specific example of the conventional phase noisecancellation method, there is a method of setting a sufficientsubcarrier spacing so that a major component of the generated phasenoise does not affect, and a method of removing a common phase noise byproviding a phase tracking reference signal (PTRS) at regular intervalsin the frequency domain and estimating an average phase.

FIG. 21 shows an example of the arrangement of PTRS that can be appliedin the NR system.

Referring to FIG. 21 , PTRSs may be arranged at regular subcarrierspacings. For example, in the NR mmWave band (e.g., 30 GHz), thesubcarrier spacing is extended from 15 kHz to 120 kHz, and PTRS of aconstant interval (e.g., 1 RE per 2 RB) may be provided. The receivingend may compensate for the phase noise in the frequency domain bycalculating the average value of the PTRS for each symbol.

With respect to PTRS, as the operating frequency increases, the phasenoise of the transmitting end increases. Here, PTRS plays an importantrole in mmWave frequency in that it can minimize the effect ofoscillator phase noise on system performance. One of the main problemswith which phase noise affects OFDM signals is the common phase rotationthat occurs for all subcarriers, which can be called to as common phasenoise (CPN) or common phase error (CPE).

The main function of PTRS is to track the phase of the local oscillatorat the transmitter and receiver. PTRS allows suppression of common phaseerrors at mmWave frequencies. PTRS may exist in both uplink and downlinkchannels. Due to the phase noise characteristics, PTRS may have a lowdensity in the frequency domain and high density in the time domain.

In an NR system, phase rotation generally affects all subcarriers in anOFDM symbol equally, but because inter-symbol correlation is low, PTRSinformation is mapped to some subcarriers per symbol. In the NR system,the PTRS can be configured according to the quality of the oscillator,the carrier frequency, the subcarrier spacing, and the modulation andcoding scheme used in transmission.

However, when the communication area changes from the mmWave band to theTHz band, the bandwidth used will be further expanded along with thechange of the frequency band, and the sampling frequency will alsoincrease accordingly.

Specifically, as the frequency of the frequency band increases, the PSDof the phase noise may increase, the degree of change of the phase noisein the time domain may increase, and the shape of the correspondingphase noise may change as the system bandwidth increases. Furthermore,in the related art, ICI of a relatively small amount does notsignificantly affect communication efficiency. However, as a frequencyband used increases, processing/cancellation of ICI may be required.

This change in the characteristics of the phase noise may also affectthe actual baseband performance. The conventional compensation forcommon phase noise is compensated by estimating the average of phasenoise that changes during the symbol period, and the degree of change(e.g., slope, variance, etc.) itself is also relatively small. On theother hand, in the THz band, since the variation within the symbolperiod is relatively large, it may not be sufficient to improvecommunication performance only by compensating for the common phasenoise. In addition, even if the above-described conventional phase noisecancellation method is applied to the THz band, a loss in performancemay occur, such as a larger signal to noise ratio (SNR) increase.

Therefore, when a frequency of a high frequency band such as THz is usedin a next-generation communication system, a decrease in communicationefficiency due to phase noise will be further aggravated, and phasenoise compensation may be an important factor affecting communicationquality in a next-generation communication system. Accordingly, thepresent disclosure proposes a method for estimating and compensating forphase noise using PTRS in order to overcome such performance loss.However, since the arrangement of the PTRS on the time-frequencyresource on the NR system is not suitable for compensating for phasenoise in a high frequency band such as THz, a new arrangement method isrequired.

FIG. 22 schematically illustrates an example in which a symbol lengthfor PTRS and a symbol length for data are set differently from eachother according to some implementations of the present disclosure.

Referring to FIG. 22 , by setting the symbol duration or symbol lengthfor PTRS to be half of the symbol duration or symbol length for data, amethod of estimating phase noise based on PTRS and compensating for achange amount of phase noise within a symbol duration for data serviceusing the estimated value may be considered. Here, as an example, if thesymbol duration for PTRS is half the symbol duration for data, thesubcarrier spacing for PTRS may be double the subcarrier spacing fordata.

The estimated phase noise may be compensated for using linearinterpolation in the time domain, and data may be reconstructed in thefrequency domain after compensation. Here, when the phase noise isestimated for each symbol for the PTRS as shown in FIG. 22 , the phasenoise can be estimated in a smaller unit than the symbol for the data,so that the phase noise compensation efficiency can be increased.

Hereinafter, the PTRS deployment methods proposed in the presentdisclosure will be described in more detail.

First, when the subcarrier spacing of the data channel and thesubcarrier spacing of the PTRS are the same, at least one of thefollowing rules may be applied.

(Rule 1-1) The symbols in which the PTRS is located are arranged atintervals of M (M is a natural number) symbol intervals.

(Rule 1-2) The start symbol in which the PTRS is located is a symbolseparated by a symbol offset from the start of the frame.

(Rule 1-3) When a resource or a location overlaps with another signal(e.g., a non-PTRS reference signal such as a demodulation referencesignal (DMRS)), the PTRS is omitted. In this case, null is also omitted.

(Rule 1-4) The resource range where the PTRS is located is limited tothe resource range to which data is allocated.

(Rule 2-1) PTRS is placed in a resource spaced apart by RE offset basedon the subcarrier position corresponding to 0 Hz.

(Rule 2-2) PTRSs are spaced apart in N*2^(n) RE units (N is a naturalnumber, n is an integer greater than or equal to 0). Here, in order toreduce the implementation burden of the UE, the UE reports itscapabilities to the base station through UE capability information,etc., so that the network can determine the PTRS arrangement method,such as determining the value of n. In this case, n may be determinedaccording to the phase locked loop (PLL) performance used by the UE.

(Rule 2-3) Based on the RE of the PTRS, a null is placed in an adjacenttone or subcarrier of the PTRS. Here, null or null data may be arrangedin a positive direction and/or a negative direction. In this case, thenumber and direction of nulls may be determined by the base station.

(Rule 2-4) A plurality of PTRSs arranged in a combination of at leastone of rules 1-1 to 1-4 and rules 2-1 to 2-3 may exist in the sameframe.

FIG. 23 schematically illustrates an example in which PTRS is deployedaccording to some implementations of the present disclosure. Here, FIG.23 is an example of a case in which the numerology for data and thenumerology for PTRS are the same.

Meanwhile, in the present disclosure, numerology may mean a subcarrierspacing. For example, the larger the number of numerology, the largerthe subcarrier spacing, and thus the length of the symbol may beshortened.

Referring to FIG. 23 , the symbol offset is 1 by rule 1-2, the RE offsetis 2 by rule 2-1, and the PTRS can be placed every symbol and every 4REs. Meanwhile, according to Rule 2-3, a null may be disposed in each REimmediately above in both directions based on the PTRS.

Here, referring to Rule 2-3, the size of the FFT at the receiving endmay be reduced through the insertion of nulls, and processing efficiencymay be increased. Specifically, referring to FIG. 23 , when PTRS andnull are FFT-transformed, the size of the FFT can be reduced by halfcompared to a case in which PTRS is allocated to a null position.

FIG. 24 schematically illustrates the structure of a receiving end of acommunication device, according to some implementations of the presentdisclosure.

Referring to FIG. 24 , a structure of a receiving end for compensatingfor phase noise based on PTRS on a received signal and performing FFTtransform on the phase noise compensated signal is illustrated. Here,the FFT transform requires a high rate of processing time in the processof processing the received signal. Therefore, there is a need for amethod for reducing the time required for FFT transform for PTRS. Inrelation to this, a method of reducing the time required for FFTtransform by reducing the FFT size through null insertion of FIG. 23 hasbeen described above. And, methods to be described later in the presentdisclosure may be additionally considered.

When the phase noise compensation method proposed in the presentdisclosure is applied, there is an advantage in that the structure ofthe receiving end of the communication device can be simplified as shownin FIG. 24 .

The receiving end may have a separate FFT block for PTRS-based phasenoise estimation, which may be 2^(n) times smaller than the size of theFFT block for data restoration according to some implementations of thepresent disclosure. In other words, the size of the FFT block for datarestoration may be 2^(n) times larger than the size of the FFT block forPTRS estimation. For example, in the case of the PTRS arrangement asshown in FIG. 23 , if 2048 FFTs are required for data, 1024 FFTs may beused as FFTs for PTRS estimation.

On the other hand, simply setting the symbol length to be short in thehigh frequency band may be a great burden in terms of processing of thereceiving UE. Accordingly, it is possible to consider a method ofcompensating for phase noise by setting the numerology for the data andthe numerology for the PTRS to be different from each other. As aspecific example, a symbol length for PTRS may be set relatively shortcompared to a symbol length for data, and a PTRS-based phase noisecompensation method in the time domain may be considered.

The subcarrier spacing of the data channel and the subcarrier spacing ofthe PTRS may be different from each other. In this case, at least one ofthe following rules may be applied.

(Rule 3-1) A separate numerology for PTRS is defined, and PTRS isarranged in the defined resource range.

At this time, in relation to the PTRS arrangement method, theabove-mentioned rules may be applied. However, the interval at which thePTRS is arranged may be M (M is a natural number) RE unit.

(Rule 3-2) Defines the numerology for data, and the data is placed inthe defined resource range.

In this case, the resource corresponding to the PTRS region defined inRule 3-1 may be excluded from the data region.

(Rule 3-3) Both Rule 3-1 and Rule 3-2 apply, and at least one of Rule3-3-1 and Rule 3-3-2, which will be described later, may additionally beapplied.

(Rule 3-3-1) Align the symbol boundary to the symbol unit of therelatively smaller side of the numerology. In other words, the boundaryof a symbol having a longer symbol length in the time domain isreferenced.

(Rule 3-3-2) In order to define the symbol duration having a relativelylarger numerology, only the data section having the smaller numerologyis used by dividing the same interval, or the entire symbol durationhaving the smaller numerology is used by dividing into equal intervals.In other words, since the symbol length having smaller numerology islonger than the symbol length having the larger numerology, a method ofarranging a plurality of data sections of a symbol having a largernumerology based on the data section of a symbol having a smallernumerology or a method of arranging a plurality of entire symboldurations of a side having a larger numerology based on the entiresymbol duration of a side having a smaller numerology may be considered.

Here, as described above, the PTRS may be spaced apart by N*2^(m) (N isa natural number, m is an integer greater than or equal to 0) RE units.Here, in order to reduce the implementation burden of the UE, the UEreports its capabilities to the base station through UE capabilityinformation, etc., so that the network can determine the PTRSarrangement method, such as determining the m value. In this case, m maybe determined according to the phase locked loop (PLL) performance usedby the UE.

FIG. 25 schematically illustrates another example in which PTRS isdeployed according to some implementations of the present disclosure.Here, FIG. 25 is an example of a case in which the numerology for dataand the numerology for PTRS are different from each other, unlike FIG.23 .

Referring to FIG. 25 , an example in which the PTRS is allocated byallocating a resource for the PTRS and the results of allocating thedata by allocating the resource for the data are combined with eachother in the resource area is shown. Here, FIG. 25 shows an example inwhich the length of one symbol in the resource region for data is thesame as the length of two symbols in the resource region for PTRS. Inother words, the numerology for PTRS in FIG. 25 has twice the size ofthe numerology for the data.

Meanwhile, referring to FIG. 25 , a first PTRS and a second PTRS may beallocated to resources to which the PTRS is allocated. Here, theconfiguration of the first PTRS and the configuration of the second PTRSmay be different from each other. Alternatively, one of the first PTRSand the second PTRS may be null.

In addition, the relationship between the numerology of data and thenumerology of PTRS can always be 2^(k). Specifically, the numerology forPTRS can always have a size of 2^(k) times that of the numerology fordata.

On the other hand, when the numerology of the resource for the PTRS andthe numerology of the resource for the data are different from eachother as shown in FIG. 25 , how to generate a cyclic prefix (CP) of theOFDM symbol may be a problem. In this regard, methods such as theexamples of FIGS. 26 and 27 may be applied.

FIG. 26 schematically illustrates an example of an OFDM signalgeneration method according to some implementations of the presentdisclosure.

According to FIG. 26 , for data symbols and PTRS symbols havingdifferent numerologies, OFDM symbols are can be configured by only thedata region excluding each CP (cyclic prefix) is first combined, andthen CP based on the combined data region is added. That is, FIG. 26 maybe an example of a method of using only the data section having thesmaller numerology of the aforementioned rule 3-3-2 by dividing as sameinterval.

Meanwhile, in the example of FIG. 26 , the correlation characteristic ofsignal processing using CP at the receiving end may be relativelybetter, but may be vulnerable to inter-symbol interference with respectto PTRS. However, considering the THz band, the effect of delay may beinsignificant.

FIG. 27 schematically illustrates another example of an OFDM signalgeneration method according to some implementations of the presentdisclosure.

According to FIG. 27 , an OFDM symbol may be configured by combining allof data symbol and all of PTRS symbol having different numerologies.That is, FIG. 27 may be an example of a method of using a symbolduration having a smaller numerology of the aforementioned rule 3-3-2 bydividing it at the same interval.

Meanwhile, as another method for reducing the FFT size, a method ofseparating a resource region for PTRS and a resource region for data maybe considered. In this case, the following rules may apply.

(Rule 4-1) After defining a resource based on numerology for PTRS, aPTRS transmission interval is defined for a specific resource. In otherwords, after defining the numerology for PTRS, a PTRS dedicated resourceinterval is defined based on the numerology.

(Rule 4-2) After defining a resource based on numerology for data, theresource used by Rule 4-1 does not allocate data. In other words, asection other than the PTRS dedicated resource section defined by Rule4-1 is defined as a data dedicated resource section.

Here, as an example, the resource region according to Rule 4-1, that is,the PTRS dedicated resource is defined by the base station, and the basestation may signal the UE to transmit information related to the PTRSdedicated resource. Meanwhile, the resources defined by the above rulesmay be commonly applied to a plurality of UEs connected to the basestation. Here, the base station can reduce signaling overhead bytransmitting the related information to a plurality of UEs in abroadcast method.

Furthermore, it is possible to reduce the size of the FFT for estimatingphase noise by separating and defining PTRS dedicated resources.Therefore, as described above, it may be more advantageous in terms ofreceiver implementation. On the other hand, since the above-mentionedrules can be applied to the PTRS arrangement method, a redundantdescription will be omitted.

FIG. 28 illustrates an example in which a PTRS dedicated resource isdefined according to some implementations of the present disclosure.

Specifically, according to FIG. 28 , PTRS dedicated resources aredefined based on 0 Hz, and resources other than PTRS dedicated resourcesmay be allocated as data dedicated resources, respectively. If the PTRSdedicated resource is defined with reference to 0 Hz, processingefficiency may be increased because there is no need to perform afrequency shift for PTRS reception.

Through this method, as described above, the size of the FFT can bereduced, and further, the burden of implementing the receiver can bereduced. In addition, referring to the above, since it is possible toestimate and compensate for PTRS-based phase noise without insertingnulls, more efficient estimation and compensation are possible.

FIG. 29 is a flowchart of an example of a method for compensating forphase noise of a UE according to some implementations of the presentdisclosure.

Referring to FIG. 29 , the UE receives a data signal and a phasetracking reference signal (PTRS) (S2910). Here, the first numerology forthe data signal and the second numerology for the PTRS may be differentfrom each other. Alternatively, the first numerology for the data signaland the second numerology for the PTRS may be the same. In this case, anull may be inserted instead of the PTRS in the resource in which thePTRS is allocated.

Thereafter, the UE estimates phase noise based on the PTRS (S2920).

Thereafter, the UE performs phase noise compensation on the data signalin the time domain based on the estimated phase noise (S2930).

Here, the above-described various embodiments, such as a method forsetting the first numerology and the second numerology, a method forarranging a PTRS, etc. can be applied to the example of FIG. 29 as well,and thus a redundant description will be omitted.

The claims described herein may be combined in various ways. Forexample, the technical features of the method claims of the presentspecification may be combined and implemented as an apparatus, and thetechnical features of the apparatus claims of the present specificationmay be combined and implemented as a method. In addition, the technicalfeatures of the method claim of the present specification and thetechnical features of the apparatus claim may be combined to beimplemented as an apparatus, and the technical features of the methodclaim of the present specification and the technical features of theapparatus claim may be combined and implemented as a method.

The methods proposed in the present specification can be performed bythe UE. In addition, the methods proposed in the present specificationcan be also performed by at least one computer-readable medium includingan instruction based on being executed by at least one processor. Themethods proposed in the present specification can be also performed byan apparatus configured to control the UE. The apparatus includes one ormore processors and one or more memories operably coupled by the one ormore processors and storing instructions, wherein the one or moreprocessors execute the instructions to perform the methods proposedherein. Also, it is obvious that, according to the methods proposed inthe present specification, an operation by the base stationcorresponding to an operation performed by the UE is considered.

Hereinafter, an example of a communication system to which the presentdisclosure is applied will be described.

Although not limited thereto, the various descriptions, functions,procedures, proposals, methods, and/or operation flowcharts of thepresent disclosure disclosed in this document may be applied to variousfields requiring wireless communication/connection (e.g., 5G) betweendevices.

Hereinafter, it will be exemplified in more detail with reference to thedrawings. In the following drawings/descriptions, the same referencenumerals may represent the same or corresponding hardware blocks,software blocks, or functional blocks, unless otherwise indicated.

FIG. 30 illustrates a communication system 1 applied to the presentdisclosure.

Referring to FIG. 30 , the communication system 1 applied to the presentdisclosure includes a wireless device, a base station, and a network.Here, the wireless device refers to a device that performs communicationusing a wireless access technology (e.g., 5G NR (New RAT), LTE (LongTerm Evolution)), and may be referred to as a communication/wireless/5Gdevice. Although not limited thereto, the wireless device may include arobot 100 a, a vehicle 100 b-1, 100 b-2, an eXtended Reality (XR) device100 c, a hand-held device 100 d, and a home appliance 100 e), anInternet of Things (IoT) device 100 f, and an AI device/server 400. Forexample, the vehicle may include a vehicle equipped with a wirelesscommunication function, an autonomous driving vehicle, a vehicle capableof performing inter-vehicle communication, and the like. Here, thevehicle may include an Unmanned Aerial Vehicle (UAV) (e.g., a drone). XRdevices include AR (Augmented Reality)/VR (Virtual Reality)/MR (MixedReality) devices, and it may be implemented in the form of aHead-Mounted Device (HMD), a Head-Up Display (HUD) provided in avehicle, a television, a smartphone, a computer, a wearable device, ahome appliance, a digital signage, a vehicle, a robot, and the like. Theportable device may include a smart phone, a smart pad, a wearabledevice (e.g., a smart watch, smart glasses), a computer (e.g., a laptopcomputer), and the like. Home appliances may include a TV, arefrigerator, a washing machine, and the like. The IoT device mayinclude a sensor, a smart meter, and the like. For example, the basestation and the network may be implemented as a wireless device, and aspecific wireless device 200 a may operate as a base station/networknode to other wireless devices.

The wireless devices 100 a to 100 f may be connected to the network 300via the BSs 200. An AI technology may be applied to the wireless devices100 a to 100 f and the wireless devices 100 a to 100 f may be connectedto the AI server 400 via the network 300. The network 300 may beconfigured using a 3G network, a 4G (e.g., LTE) network, or a 5G (e.g.,NR) network. Although the wireless devices 100 a to 100 f maycommunicate with each other through the BSs 200/network 300, thewireless devices 100 a to 100 f may perform direct communication (e.g.,sidelink communication) with each other without passing through theBSs/network. For example, the vehicles 100 b-1 and 100 b-2 may performdirect communication (e.g. Vehicle-to-Vehicle(V2V)/Vehicle-to-everything (V2X) communication). In addition, the IoTdevice (e.g., a sensor) may perform direct communication with other IoTdevices (e.g., sensors) or other wireless devices 100 a to 100 f.

Wireless communication/connections 150 a, 150 b, or 150 c may beestablished between the wireless devices 100 a to 100 f/BS 200, or BS200/BS 200. Herein, the wireless communication/connections may beestablished through various RATs (e.g., 5G NR) such as uplink/downlinkcommunication 150 a, sidelink communication 150 b (or, D2Dcommunication), or inter BS communication (e.g. relay, Integrated AccessBackhaul (IAB)). The wireless devices and the BSs/the wireless devicesmay transmit/receive radio signals to/from each other through thewireless communication/connections 150 a and 150 b. For example, thewireless communication/connections 150 a and 150 b may transmit/receivesignals through various physical channels. To this end, at least a partof various configuration information configuring processes, varioussignal processing processes (e.g., channel encoding/decoding,modulation/demodulation, and resource mapping/demapping), and resourceallocating processes, for transmitting/receiving radio signals, may beperformed based on the various proposals of the present disclosure.

Meanwhile, NR supports multiple numerologies (or subcarrier spacing(SCS)) for supporting diverse 5G services. For example, if the SCS is 15kHz, a wide area of the conventional cellular bands may be supported. Ifthe SCS is 30 kHz/60 kHz, a dense-urban, lower latency, and widercarrier bandwidth is supported. If the SCS is 60 kHz or higher, abandwidth greater than 24.25 GHz is used in order to overcome phasenoise.

An NR frequency band may be defined as a frequency range of two types(FR1, FR2). Values of the frequency range may be changed. For example,the frequency range of the two types (FR1, FR2) may be as shown below inTable 7. For convenience of explanation, among the frequency ranges thatare used in an NR system, FR1 may mean a “sub 6 GHz range”, and FR2 maymean an “above 6 GHz range” and may also be referred to as a millimeterwave (mmW).

TABLE 7 Frequency Range Corresponding Subcarrier Spacing designationfrequency range (SCS) FR1  450 MHz-6000 MHz  15, 30, 60 kHz FR2 24250MHz-52600 MHz 60, 120, 240 kHz

As described above, the values of the frequency ranges in the NR systemmay be changed. For example, as shown in Table 8 below, FR1 may includea band in the range of 410 MHz to 7125 MHz. That is, FR1 may include afrequency band of at least 6 GHz (or 5850, 5900, 5925 MHz, and so on).For example, a frequency band of at least 6 GHz (or 5850, 5900, 5925MHz, and so on) included in FR1 may include an unlicensed band. Theunlicensed band may be used for diverse purposes, e.g., the unlicensedband for vehicle-specific communication (e.g., automated driving).

TABLE 8 Frequency Range Corresponding Subcarrier Spacing designationfrequency range (SCS) FR1  410 MHz-7125 MHz  15, 30, 60 kHz FR2 24250MHz-52600 MHz 60, 120, 240 kHz

Hereinafter, an example of a wireless device to which the presentdisclosure is applied will be described.

FIG. 31 illustrates a wireless device applicable to the presentdisclosure.

Referring to FIG. 31 , the first wireless device 100 and the secondwireless device 200 may transmit and receive wireless signals throughvarious wireless access technologies (e.g., LTE, NR). Here, {firstwireless device 100, second wireless device 200} may correspond to{wireless device 100 x, base station 200} and/or {wireless device 100 x,wireless device 100 x} of FIG. 30 .

The first wireless device 100 may include one or more processors 102 andone or more memories 104 and additionally further include one or moretransceivers 106 and/or one or more antennas 108. The processors 102 maycontrol the memory 104 and/or the transceivers 106 and may be configuredto implement the descriptions, functions, procedures, proposals,methods, and/or operational flowcharts disclosed in this document. Forexample, the processors 102 may process information within the memory104 to generate first information/signals and then transmit radiosignals including the first information/signals through the transceivers106. In addition, the processor 102 may receive radio signals includingsecond information/signals through the transceiver 106 and then storeinformation obtained by processing the second information/signals in thememory 104. The memory 104 may be connected to the processory 102 andmay store a variety of information related to operations of theprocessor 102. For example, the memory 104 may store software codeincluding commands for performing a part or the entirety of processescontrolled by the processor 102 or for performing the descriptions,functions, procedures, proposals, methods, and/or operational flowchartsdisclosed in this document. Herein, the processor 102 and the memory 104may be a part of a communication modem/circuit/chip designed toimplement RAT (e.g., LTE or NR). The transceiver 106 may be connected tothe processor 102 and transmit and/or receive radio signals through oneor more antennas 108. The transceiver 106 may include a transmitterand/or a receiver. The transceiver 106 may be interchangeably used witha radio frequency (RF) unit. In the present disclosure, the wirelessdevice may represent a communication modem/circuit/chip.

The second wireless device 200 may include one or more processors 202and one or more memories 204 and additionally further include one ormore transceivers 206 and/or one or more antennas 208. The processor 202may control the memory 204 and/or the transceiver 206 and may beconfigured to implement the descriptions, functions, procedures,proposals, methods, and/or operational flowcharts disclosed in thisdocument. For example, the processor 202 may process information withinthe memory 204 to generate third information/signals and then transmitradio signals including the third information/signals through thetransceiver 206. In addition, the processor 202 may receive radiosignals including fourth information/signals through the transceiver 106and then store information obtained by processing the fourthinformation/signals in the memory 204. The memory 204 may be connectedto the processor 202 and may store a variety of information related tooperations of the processor 202. For example, the memory 204 may storesoftware code including commands for performing a part or the entiretyof processes controlled by the processor 202 or for performing thedescriptions, functions, procedures, proposals, methods, and/oroperational flowcharts disclosed in this document. Herein, the processor202 and the memory 204 may be a part of a communicationmodem/circuit/chip designed to implement RAT (e.g., LTE or NR). Thetransceiver 206 may be connected to the processor 202 and transmitand/or receive radio signals through one or more antennas 208. Thetransceiver 206 may include a transmitter and/or a receiver. Thetransceiver 206 may be interchangeably used with an RF unit. In thepresent disclosure, the wireless device may represent a communicationmodem/circuit/chip.

Hereinafter, hardware elements of the wireless devices 100 and 200 willbe described more specifically. One or more protocol layers may beimplemented by, without being limited to, one or more processors 102 and202. For example, the one or more processors 102 and 202 may implementone or more layers (e.g., functional layers such as PHY, MAC, RLC, PDCP,RRC, and SDAP). The one or more processors 102 and 202 may generate oneor more Protocol Data Units (PDUs) and/or one or more Service Data Unit(SDUs) according to the descriptions, functions, procedures, proposals,methods, and/or operational flowcharts disclosed in this document. Theone or more processors 102 and 202 may generate messages, controlinformation, data, or information according to the descriptions,functions, procedures, proposals, methods, and/or operational flowchartsdisclosed in this document. The one or more processors 102 and 202 maygenerate signals (e.g., baseband signals) including PDUs, SDUs,messages, control information, data, or information according to thedescriptions, functions, procedures, proposals, methods, and/oroperational flowcharts disclosed in this document and provide thegenerated signals to the one or more transceivers 106 and 206. The oneor more processors 102 and 202 may receive the signals (e.g., basebandsignals) from the one or more transceivers 106 and 206 and acquire thePDUs, SDUs, messages, control information, data, or informationaccording to the descriptions, functions, procedures, proposals,methods, and/or operational flowcharts disclosed in this document.

The one or more processors 102 and 202 may be referred to ascontrollers, microcontrollers, microprocessors, or microcomputers. Theone or more processors 102 and 202 may be implemented by hardware,firmware, software, or a combination thereof. For example, one or moreApplication Specific Integrated Circuits (ASICs), one or more DigitalSignal Processors (DSPs), one or more Digital Signal Processing Devices(DSPDs), one or more Programmable Logic Devices (PLDs), or one or moreField Programmable Gate Arrays (FPGAs) may be included in the one ormore processors 102 and 202. The descriptions, functions, procedures,proposals, methods, and/or operational flowcharts disclosed in thisdocument may be implemented using firmware or software and the firmwareor software may be configured to include the modules, procedures, orfunctions. Firmware or software configured to perform the descriptions,functions, procedures, proposals, methods, and/or operational flowchartsdisclosed in this document may be included in the one or more processors102 and 202 or stored in the one or more memories 104 and 204 so as tobe driven by the one or more processors 102 and 202. The descriptions,functions, procedures, proposals, methods, and/or operational flowchartsdisclosed in this document may be implemented using firmware or softwarein the form of code, commands, and/or a set of commands.

The one or more memories 104 and 204 may be connected to the one or moreprocessors 102 and 202 and store various types of data, signals,messages, information, programs, code, instructions, and/or commands.The one or more memories 104 and 204 may be configured by Read-OnlyMemories (ROMs), Random Access Memories (RAMs), Electrically ErasableProgrammable Read-Only Memories (EPROMs), flash memories, hard drives,registers, cash memories, computer-readable storage media, and/orcombinations thereof. The one or more memories 104 and 204 may belocated at the interior and/or exterior of the one or more processors102 and 202. In addition, the one or more memories 104 and 204 may beconnected to the one or more processors 102 and 202 through varioustechnologies such as wired or wireless connection.

The one or more transceivers 106 and 206 may transmit user data, controlinformation, and/or radio signals/channels, mentioned in the methodsand/or operational flowcharts of this document, to one or more otherdevices. The one or more transceivers 106 and 206 may receive user data,control information, and/or radio signals/channels, mentioned in thedescriptions, functions, procedures, proposals, methods, and/oroperational flowcharts disclosed in this document, from one or moreother devices. For example, the one or more transceivers 106 and 206 maybe connected to the one or more processors 102 and 202 and transmit andreceive radio signals. For example, the one or more processors 102 and202 may perform control so that the one or more transceivers 106 and 206may transmit user data, control information, or radio signals to one ormore other devices. In addition, the one or more processors 102 and 202may perform control so that the one or more transceivers 106 and 206 mayreceive user data, control information, or radio signals from one ormore other devices. In addition, the one or more transceivers 106 and206 may be connected to the one or more antennas 108 and 208 and the oneor more transceivers 106 and 206 may be configured to transmit andreceive user data, control information, and/or radio signals/channels,mentioned in the descriptions, functions, procedures, proposals,methods, and/or operational flowcharts disclosed in this document,through the one or more antennas 108 and 208. In this document, the oneor more antennas may be a plurality of physical antennas or a pluralityof logical antennas (e.g., antenna ports). The one or more transceivers106 and 206 may convert received radio signals/channels etc. from RFband signals into baseband signals in order to process received userdata, control information, radio signals/channels, etc. using the one ormore processors 102 and 202. The one or more transceivers 106 and 206may convert the user data, control information, radio signals/channels,etc. processed using the one or more processors 102 and 202 from thebase band signals into the RF band signals. To this end, the one or moretransceivers 106 and 206 may include (analog) oscillators and/orfilters.

Hereinafter, an example of a signal processing circuit to which thepresent disclosure is applied will be described.

FIG. 32 exemplifies a signal processing circuit for a transmissionsignal.

Referring to FIG. 32 , a signal processing circuit 1000 includes ascrambler 1010, a modulator 1020, a layer mapper 1030, a precoder 1040,a resource mapper 1050, and a signal generator 1060. Theoperations/functions of FIG. 32 may be performed in the processors 102and 202 and/or the transceivers 106 and 206 of FIG. 31 but are notlimited thereto. The hardware elements of FIG. 32 may be implemented inthe processors 102 and 202 and/or the transceivers 106 and 206 of FIG.31 . For example, blocks 1010 to 1060 may be implemented in theprocessors 102 and 202 of FIG. 31 . In addition, blocks 1010 to 1050 maybe implemented in the processors 102 and 202 of FIG. 31 , and block 1060may be implemented in the transceivers 106 and 206 of FIG. 31 .

A codeword may be converted into a wireless signal through the signalprocessing circuit 1000 of FIG. 32 . Here, the codeword is an encodedbit sequence of an information block. The information block may includea transport block (e.g., a UL-SCH transport block or a DL-SCH transportblock). The wireless signal may be transmitted through various physicalchannels (e.g., PUSCH or PDSCH).

Specifically, the codeword may be converted into a scrambled bitsequence by the scrambler 1010. The scramble sequence used forscrambling is generated based on an initialization value, and theinitialization value may include ID information of a wireless device.The scrambled bit sequence may be modulated by the modulator 1020 into amodulation symbol sequence. The modulation scheme may includepi/2-binary phase shift keying (pi/2-BPSK), m-phase shift keying(m-PSK), m-quadrature amplitude modulation (m-QAM), and the like. Thecomplex modulation symbol sequence may be mapped to one or moretransport layers by the layer mapper 1030. The modulation symbols ofeach transport layer may be mapped to the corresponding antenna port(s)by the precoder 1040 (precoding). An output z of the precoder 1040 maybe obtained by multiplying an output y of the layer mapper 1030 by anN*M precoding matrix W. Here, N is the number of antenna ports and M isthe number of transmission layers. Here, the precoder 1040 may performprecoding after performing transform precoding (e.g., DFT transform) oncomplex modulation symbols. Also, the precoder 1040 may performprecoding without performing transform precoding.

The resource mapper 1050 may map modulation symbols of each antenna portto a time-frequency resource. The time-frequency resource may include aplurality of symbols (e.g., CP-OFDMA symbols or DFT-s-OFDMA symbols) ina time domain and may include a plurality of subcarriers in a frequencydomain. The signal generator 1060 may generate a wireless signal fromthe mapped modulation symbols, and the generated wireless signal may betransmitted to another device through each antenna. To this end, thesignal generator 1060 may include an inverse fast Fourier transform(IFFT) module, a cyclic prefix (CP) inserter, a digital-to-analogconverter (DAC), a frequency uplink converter, and the like.

A signal processing process for a received signal in the wireless devicemay be configured as the reverse of the signal processing process (1010to 1060) of FIG. 32 . For example, a wireless device (e.g., 100 or 200in FIG. 31 ) may receive a wireless signal from the outside through anantenna port/transmitter. The received wireless signal may be convertedinto a baseband signal through a signal restorer. To this end, thesignal restorer may include a frequency downlink converter, ananalog-to-digital converter (ADC), a CP canceller, and a fast Fouriertransform (FFT) module. Thereafter, the baseband signal may be restoredinto a codeword through a resource de-mapper process, a postcodingprocess, a demodulation process, and a de-scramble process. The codewordmay be restored to an original information block through decoding.Accordingly, a signal processing circuit (not shown) for a receivedsignal may include a signal restorer, a resource demapper, a postcoder,a demodulator, a descrambler, and a decoder.

Hereinafter, an example of utilization of a wireless device to which thepresent disclosure is applied will be described.

FIG. 33 shows another example of a wireless device applied to thepresent disclosure. The wireless device can be implemented in variousforms according to use-examples/services (Refer to FIG. 30 ).

Referring to FIG. 33 , wireless devices (100, 200) may correspond to thewireless devices (100, 200) of FIG. 31 and may be configured by variouselements, components, units/portions, and/or modules. For example, eachof the wireless devices (100, 200) may include a communication unit(110), a control unit (120), a memory unit (130), and additionalcomponents (140). The communication unit may include a communicationcircuit (112) and transceiver(s) (114). For example, the communicationcircuit (112) may include the one or more processors (102, 202) and/orthe one or more memories (104, 204) of FIG. 31 . For example, thetransceiver(s) (114) may include the one or more transceivers (106, 206)and/or the one or more antennas (108, 208) of FIG. 31 . The control unit(120) is electrically connected to the communication unit (110), thememory (130), and the additional components (140) and controls overalloperation of the wireless devices. For example, the control unit (120)may control an electric/mechanical operation of the wireless devicebased on programs/code/instructions/information stored in the memoryunit (130). The control unit (120) may transmit the information storedin the memory unit (130) to the exterior (e.g., other communicationdevices) via the communication unit (110) through a wireless/wiredinterface or store, in the memory unit (130), information receivedthrough the wireless/wired interface from the exterior (e.g., othercommunication devices) via the communication unit (110).

The additional components (140) may be variously configured according totypes of wireless devices. For example, the additional components (140)may include at least one of a power unit/battery, input/output (I/O)unit, a driving unit, and a computing unit. The wireless device may beimplemented in the form of, without being limited to, the robot (100 aof FIG. 30 ), the vehicles (100 b-1, 100 b-2 of FIG. 30 ), the XR device(100 c of FIG. 30 ), the hand-held device (100 d of FIG. 30 ), the homeappliance (100 e of FIG. 30 ), the IoT device (100 f of FIG. 30 ), adigital broadcast UE, a hologram device, a public safety device, an MTCdevice, a medicine device, a fintech device (or a finance device), asecurity device, a climate/environment device, the AI server/device (400of FIG. 30 ), the BSs (200 of FIG. 30 ), a network node, and so on. Thewireless device may be used in a mobile or fixed place according to ausage-example/service.

In FIG. 33 , the entirety of the various elements, components,units/portions, and/or modules in the wireless devices (100, 200) may beconnected to each other through a wired interface or at least a partthereof may be wirelessly connected through the communication unit(110). For example, in each of the wireless devices (100, 200), thecontrol unit (120) and the communication unit (110) may be connected bywire and the control unit (120) and first units (e.g., 130, 140) may bewirelessly connected through the communication unit (110). Each element,component, unit/portion, and/or module within the wireless devices (100,200) may further include one or more elements. For example, the controlunit (120) may be configured by a set of one or more processors. As anexample, the control unit (120) may be configured by a set of acommunication control processor, an application processor, an ElectronicControl Unit (ECU), a graphical processing unit, and a memory controlprocessor. As another example, the memory (130) may be configured by aRandom Access Memory (RAM), a Dynamic RAM (DRAM), a Read Only Memory(ROM)), a flash memory, a volatile memory, a non-volatile memory, and/ora combination thereof.

Hereinafter, an example of implementing FIG. 33 will be described indetail with reference to the drawings.

Hereinafter, an example of a mobile device to which the presentdisclosure is applied will be described.

FIG. 34 illustrates a portable device applied to the present disclosure.The portable device may include a smartphone, a smart pad, a wearabledevice (e.g., smart watch or smart glasses), a portable computer (e.g.,a notebook), etc. The portable device may be referred to as a mobilestation (MS), a user terminal (UT), a mobile subscriber station (MSS), asubscriber station (SS), an advanced mobile station (AMS), or a wirelessterminal (WT).

Referring to FIG. 34 , the portable device 100 may include an antennaunit 108, a communication unit 110, a controller 120, a memory unit 130,a power supply unit 140 a, an interface unit 140 b, and input/outputunit 140 c. The antenna unit 108 may be configured as a part of thecommunication unit 110. Blocks 110 to 130/140 a to 140 c correspond toblocks 110 to 130/140 of FIG. 33 , respectively.

The communication unit 110 may transmit and receive signals (e.g., data,control signals, etc.) with other wireless devices and BSs. Thecontroller 120 may perform various operations by controlling componentsof the portable device 100. The controller 120 may include anapplication processor (AP). The memory unit 130 may storedata/parameters/programs/codes/commands required for driving theportable device 100. Also, the memory unit 130 may store input/outputdata/information, and the like. The power supply unit 140 a suppliespower to the portable device 100 and may include a wired/wirelesscharging circuit, a battery, and the like. The interface unit 140 b maysupport connection between the portable device 100 and other externaldevices. The interface unit 140 b may include various ports (e.g., audioinput/output ports or video input/output ports) for connection withexternal devices. The input/output unit 140 c may receive or outputimage information/signal, audio information/signal, data, and/orinformation input from a user. The input/output unit 140 c may include acamera, a microphone, a user input unit, a display unit 140 d, aspeaker, and/or a haptic module.

For example, in the case of data communication, the input/output unit140 c acquires information/signals (e.g., touch, text, voice, image, orvideo) input from the user, and the acquired information/signals may bestored in the memory unit 130. The communication unit 110 may convertinformation/signals stored in the memory into wireless signals and maydirectly transmit the converted wireless signals to other wirelessdevices or to a BS. In addition, after receiving a wireless signal fromanother wireless device or a BS, the communication unit 110 may restorethe received wireless signal to the original information/signal. Therestored information/signal may be stored in the memory unit 130 andthen output in various forms (e.g., text, voice, image, video, orhaptic) through the input/output unit 140 c.

Hereinafter, an example of a vehicle to which the present disclosure isapplied or an autonomous driving vehicle will be described.

FIG. 35 illustrates a vehicle or an autonomous vehicle applied to thepresent disclosure. A vehicle or an autonomous vehicle may beimplemented as a moving robot, a vehicle, a train, an aerial vehicle(AV), a ship, or the like.

Referring to FIG. 35 , a vehicle or autonomous vehicle 100 includes anantenna unit 108, a communication unit 110, a control unit 120, adriving unit 140 a, a power supply unit 140 b, and a sensor unit 140 c,and an autonomous driving unit 140 d. The antenna unit 108 may beconfigured as a portion of the communication unit 110. Blocks110/130/140 a to 140 d correspond to blocks 110/130/140 of FIG. 33 ,respectively.

The communication unit 110 may transmit and receive signals (e.g., data,control signals, etc.) with external devices such as other vehicles,base stations (BSs) (e.g. base station, roadside unit, etc.), andservers. The control unit 120 may perform various operations bycontrolling elements of the vehicle or the autonomous vehicle 100. Thecontrol unit 120 may include an electronic control unit (ECU). Thedriving unit 140 a may cause the vehicle or the autonomous vehicle 100to travel on the ground. The driving unit 140 a may include an engine, amotor, a power train, a wheel, a brake, a steering device, and the like.The power supply unit 140 b supplies power to the vehicle or theautonomous vehicle 100, and may include a wired/wireless chargingcircuit, a battery, and the like. The sensor unit 140 c may obtainvehicle status, surrounding environment information, user information,and the like. The sensor unit 140 c may include an inertial measurementunit (IMU) sensor, a collision sensor, a wheel sensor, a speed sensor,an inclination sensor, a weight detection sensor, a heading sensor, aposition module, a vehicle forward/reverse sensor, a battery sensor, afuel sensor, a tire sensor, a steering sensor, a temperature sensor, ahumidity sensor, an ultrasonic sensor, an illuminance sensor, a pedalposition sensor, etc. The autonomous driving unit 140 d may implement atechnology of maintaining a driving lane, a technology of automaticallyadjusting a speed such as adaptive cruise control, a technology ofautomatically traveling along a predetermined route, and a technology ofautomatically setting a route and traveling when a destination is set.

For example, the communication unit 110 may receive map data, trafficinformation data, and the like from an external server. The autonomousdriving unit 140 d may generate an autonomous driving route and adriving plan based on the acquired data. The control unit 120 maycontrol the driving unit 140 a so that the vehicle or the autonomousvehicle 100 moves along the autonomous driving route according to thedriving plan (e.g., speed/direction adjustment). During autonomousdriving, the communication unit 110 may asynchronously/periodicallyacquire the latest traffic information data from an external server andmay acquire surrounding traffic information data from surroundingvehicles. In addition, during autonomous driving, the sensor unit 140 cmay acquire vehicle state and surrounding environment information. Theautonomous driving unit 140 d may update the autonomous driving routeand the driving plan based on newly acquired data/information. Thecommunication unit 110 may transmit information on a vehicle location,an autonomous driving route, a driving plan, and the like to theexternal server. The external server may predict traffic informationdata in advance using AI technology or the like based on informationcollected from the vehicle or autonomous vehicles and may provide thepredicted traffic information data to the vehicle or autonomousvehicles.

Hereinafter, examples of AR/VR and vehicles to which the presentdisclosure is applied will be described.

FIG. 36 illustrates a vehicle applied to the present disclosure.Vehicles may also be implemented as means of transportation, trains,aircraft, and ships.

Referring to FIG. 36 , the vehicle 100 may include a communication unit110, a control unit 120, a memory unit 130, an input/output unit 140 a,and a position measurement unit 140 b. Here, blocks 110 to 130/140 a to140 d correspond to blocks 110 to 130/140 of FIG. 33 , respectively.

The communication unit 110 may transmit and receive signals (e.g., data,control signals, etc.) with other vehicles or external devices such as aBS. The control unit 120 may perform various operations by controllingcomponents of the vehicle 100. The memory unit 130 may storedata/parameters/programs/codes/commands supporting various functions ofthe vehicle 100. The input/output unit 140 a may output an AR/VR objectbased on information in the memory unit 130. The input/output unit 140 amay include a HUD. The location measurement unit 140 b may acquirelocation information of the vehicle 100. The location information mayinclude absolute location information of the vehicle 100, locationinformation within a driving line, acceleration information, locationinformation with surrounding vehicles, and the like. The locationmeasurement unit 140 b may include a GPS and various sensors.

For example, the communication unit 110 of the vehicle 100 may receivemap information, traffic information, etc., from an external server andstore the information in the memory unit 130. The location measurementunit 140 b may acquire vehicle location information through GPS andvarious sensors and store the vehicle location information in the memoryunit 130. The control unit 120 may generate a virtual object based theon map information, the traffic information, the vehicle locationinformation, and the like, and the input/output unit 140 a may displaythe generated virtual object on a window of the vehicle (1410, 1420). Inaddition, the control unit 120 may determine whether the vehicle 100 isoperating normally within a driving line based on vehicle locationinformation. When the vehicle 100 deviates from the driving lineabnormally, the control unit 120 may display a warning on a windshieldof the vehicle through the input/output unit 140 a. In addition, thecontrol unit 120 may broadcast a warning message regarding a drivingabnormality to nearby vehicles through the communication unit 110.Depending on a situation, the control unit 120 may transmit locationinformation of the vehicle and information on driving/vehicleabnormalities to related organizations through the communication unit110.

Hereinafter, an example of an XR device to which the present disclosureis applied will be described.

FIG. 37 illustrates an XR device applied to the present disclosure. TheXR device may be implemented as an HMD, a head-up display (HUD) providedin a vehicle, a television, a smartphone, a computer, a wearable device,a home appliance, a digital signage, a vehicle, a robot, and the like.

Referring to FIG. 37 , the XR device 100 a may include a communicationunit 110, a control unit 120, a memory unit 130, an input/output unit140 a, a sensor unit 140 b, and a power supply unit 140 c. Here, blocks110 to 130/140 a to 140 c correspond to blocks 110 to 130/140 of FIG. 33, respectively.

The communication unit 110 may transmit and receive signals (e.g., mediadata, control signals, etc.) with external devices such as otherwireless devices, portable devices, media servers. Media data mayinclude images, sounds, and the like. The control unit 120 may performvarious operations by controlling components of the XR device 100 a. Forexample, the control unit 120 may be configured to control and/orperform procedures such as video/image acquisition, (video/image)encoding, and metadata generating and processing. The memory unit 130may store data/parameters/programs/codes/commands required for drivingthe XR device 100 a/generating an XR object. The input/output unit 140 amay obtain control information, data, etc. from the outside and mayoutput the generated XR object. The input/output unit 140 a may includea camera, a microphone, a user input unit, a display unit, a speaker,and/or a haptic module. The sensor unit 140 b may obtain XR devicestatus, surrounding environment information, user information, and thelike. The sensor unit 140 b may include a proximity sensor, anilluminance sensor, an acceleration sensor, a magnetic sensor, a gyrosensor, an inertial sensor, an RGB sensor, an IR sensor, a fingerprintrecognition sensor, an ultrasonic sensor, an optical sensor, amicrophone, and/or a radar. The power supply unit 140 c may supply powerto the XR device 100 a and may include a wired/wireless chargingcircuit, a battery, and the like.

As an example, the memory unit 130 of the XR device 100 a may includeinformation (e.g., data, etc.) necessary for generating an XR object(e.g., AR/VR/MR object). The input/output unit 140 a may acquire acommand to manipulate the XR device 100 a from a user, and the controlunit 120 may drive the XR device 100 a according to the user's drivingcommand. For example, when the user tries to watch a movie, news, etc.,through the XR device 100 a, the control unit 120 may transmit contentrequest information through the communication unit 130 to another device(for example, the portable device 100 b) or to a media server. Thecommunication unit 130 may download/stream content such as movies andnews from another device (e.g., the portable device 100 b) or the mediaserver to the memory unit 130. The control unit 120 may control and/orperform procedures such as video/image acquisition, (video/image)encoding, and metadata generating/processing for the content, andgenerate/output an XR object based on information on a surrounding spaceor a real object through the input/output unit 140 a/sensor unit 140 b.

In addition, the XR device 100 a may be wirelessly connected to theportable device 100 b through the communication unit 110, and anoperation of the XR device 100 a may be controlled by the portabledevice 100 b. For example, the portable device 100 b may operate as acontroller for the XR device 100 a. To this end, the XR device 100 a mayacquire 3D location information of the portable device 100 b, generatean XR entity corresponding to the portable device 100 b, and output thegenerated XR entity.

Hereinafter, an example of a robot to which the present disclosure isapplied will be described.

FIG. 38 illustrates a robot applied to the present disclosure. Robotsmay be classified as industrial, medical, household, military, etc.depending on the purpose or field of use.

Referring to FIG. 38 , a robot 100 may include a communication unit 110,a control unit 120, a memory unit 130, an input/output unit 140 a, asensor unit 140 b, and a driving unit 140 c. Here, blocks 110 to 130/140a to 140 d correspond to blocks 110 to 130/140 of FIG. 33 ,respectively.

The communication unit 110 may transmit and receive signals (e.g.,driving information, control signals, etc.) with other wireless devices,other robots, or external devices such as a control server. The controlunit 120 may perform various operations by controlling components of therobot 100. The memory unit 130 may storedata/parameters/programs/codes/commands supporting various functions ofthe robot 100. The input/output unit 140 a may acquire information fromthe outside of the robot 100 and may output the information to theoutside of the robot 100. The input/output unit 140 a may include acamera, a microphone, a user input unit, a display unit, a speaker,and/or a haptic module. The sensor unit 140 b may obtain internalinformation, surrounding environment information, user information, andthe like of the robot 100. The sensor unit 140 b may include a proximitysensor, an illuminance sensor, an acceleration sensor, a magneticsensor, a gyro sensor, an inertial sensor, an IR sensor, a fingerprintrecognition sensor, an ultrasonic sensor, an optical sensor, amicrophone, a radar, and the like. The driving unit 140 c may performvarious physical operations such as moving a robot joint. In addition,the driving unit 140 c may cause the robot 100 to travel on the groundor fly in the air. The driving unit 140 c may include an actuator, amotor, a wheel, a brake, a propeller, and the like.

Hereinafter, an example of an AI device to which the present disclosureis applied will be described.

FIG. 39 illustrates an AI device applied to the present disclosure. AIdevices may be implemented as fixed devices or moving devices such asTVs, projectors, smartphones, PCs, notebooks, digital broadcasting UEs,tablet PCs, wearable devices, set-top boxes (STBs), radios, washingmachines, refrigerators, digital signage, robots, vehicles, etc.

Referring to FIG. 39 , the AI device 100 may include a communicationunit 110, a control unit 120, a memory unit 130, an input/output unit140 a/140 b, a learning processor unit 140 c, and a sensor unit. Blocks110 to 130/140 a to 140 d correspond to blocks 110 to 130/140 of FIG. 33, respectively.

The communication unit 110 may transmit and receive wireless signals(e.g., sensor information, user input, learning model, control signals,etc.) with external devices such as another AI device (e.g., FIG. 30,100 x, 200, or 400) or an AI server (e.g., 400 in FIG. 30 ) usingwired/wireless communication technology. To this end, the communicationunit 110 may transmit information in the memory unit 130 to an externaldevice or may transfer a signal received from the external device to thememory unit 130.

The control unit 120 may determine at least one executable operation ofthe AI device 100 based on information determined or generated using adata analysis algorithm or a machine learning algorithm. In addition,the control unit 120 may perform a determined operation by controllingthe components of the AI device 100. For example, the control unit 120may request, search, receive, or utilize data from the learningprocessor unit 140 c or the memory unit 130, and may control componentsof the AI device 100 to execute a predicted operation among at least onean executable operation or an operation determined to be desirable. Inaddition, the control unit 120 may collect history information includingoperation content of the AI device 100 or the user's feedback on theoperation, and store the collected information in the memory unit 130 orthe learning processor unit 140 c or transmit the information to anexternal device such as an AI server (400 of FIG. 30 ). The collectedhistorical information may be used to update a learning model.

The memory unit 130 may store data supporting various functions of theAI device 100. For example, the memory unit 130 may store data obtainedfrom the input unit 140 a, data obtained from the communication unit110, output data from the learning processor unit 140 c, and dataobtained from the sensing unit 140. In addition, the memory unit 130 maystore control information and/or software codes necessary for theoperation/execution of the control unit 120.

The input unit 140 a may acquire various types of data from the outsideof the AI device 100. For example, the input unit 140 a may acquiretraining data for model training and input data to which the trainingmodel is applied. The input unit 140 a may include a camera, amicrophone, and/or a user input unit. The output unit 140 b may generateoutput related to visual, auditory, or tactile sense. The output unit140 b may include a display unit, a speaker, and/or a haptic module. Thesensing unit 140 may obtain at least one of internal information of theAI device 100, surrounding environment information of the AI device 100,and user information by using various sensors. The sensing unit 140 mayinclude a proximity sensor, an illuminance sensor, an accelerationsensor, a magnetic sensor, a gyro sensor, an inertial sensor, an RGBsensor, an IR sensor, a fingerprint recognition sensor, an ultrasonicsensor, an optical sensor, a microphone, and/or a radar.

The learning processor unit 140 c may train a model configured as anartificial neural network using training data. The learning processorunit 140 c may perform AI processing together with the learningprocessor unit (400 in FIG. 30 ) of the AI server. The learningprocessor unit 140 c may process information received from an externaldevice through the communication unit 110 and/or information stored inthe memory unit 130. In addition, an output value of the learningprocessor unit 140 c may be transmitted to an external device throughthe communication unit 110 and/or may be stored in the memory unit 130.

1. A method of performing phase noise compensation by a user equipment(UE) in a wireless communication system, the method comprising:receiving a data signal and a phase tracking reference signal (PTRS),wherein the data signal is transmitted based on a first numerology andthe PTRS is transmitted based on a second numerology; estimating phasenoise based on the PTRS; and performing the phase noise compensation onthe data signal in a time domain based on the estimated phase noise. 2.The method of claim 1, wherein the UE receives the data signal and thePTRS at the same time.
 3. The method of claim 1, wherein the secondnumerology is greater than the first numerology.
 4. The method of claim3, wherein the second numerology is 2^(n) times greater than the firstnumerology, and wherein n is an integer of 1 or more.
 5. The method ofclaim 4, wherein a first data region in a first symbol for the firstnumerology is 2^(n) times longer than a second data region in a secondsymbol for the second numerology.
 6. The method of claim 5, wherein acyclic prefix (CP) of a third symbol in which the data signal and thePTRS are transmitted is configured based on a sum of the first dataregion and the second data region.
 7. The method of claim 6, wherein alength of a third data region in the third symbol is a same as a lengthof the first data region, and wherein the third data region is expressedas a sum of the first data region and 2^(n) number of the second dataregions in a time domain.
 8. The method of claim 4, wherein a firstsymbol length for the first numerology is 2^(n) times longer than asecond symbol length for the second numerology.
 9. The method of claim8, wherein a length of a fourth symbol in which the data signal and thePTRS are transmitted is a same as a length of the first symbol, andwherein the fourth symbol is represented by a sum of the first symboland the 2^(n) second symbols in a time domain.
 10. The method of claim1, wherein the first numerology and second numerology are a same as eachother, and wherein null is allocated to a resource element adjacent to aresource element (RE) to which the PTRS is allocated.
 11. The method ofclaim 1, wherein a first time-frequency resource region to which thedata signal is allocated and a second time-frequency resource region towhich the PTRS is allocated do not overlap each other.
 12. The method ofclaim 11, wherein the second time-frequency resource region comprises a0 Hz resource element (resource element: RE).
 13. The method of claim12, wherein the first numerology and the second numerology are a same asor different from each other.
 14. The method of claim 12, whereininformation for the first time-frequency resource region and the secondtime-frequency resource region is broadcast by a base station.
 15. Auser equipment (UE), the UE comprising: at least one memory storinginstructions; at least one transceiver; and at least one processorcoupling the at least one memory and the at least one transceiver,wherein the at least one processor execute the instructions, wherein theat least one processor: receives a data signal and a phase trackingreference signal (PTRS), wherein the data signal is transmitted based ona first numerology and the PTRS is transmitted based on a secondnumerology; estimates phase noise based on the PTRS; and performs thephase noise compensation on the data signal in a time domain based onthe estimated phase noise.
 16. The UE of claim 15, wherein the UE has aFast Fourier Transformation (FFT) block dedicated to the data signal anda FFT block dedicated to the PTRS.
 17. An apparatus configured tocontrol a user equipment (UE), the apparatus comprising: at least oneprocessor; and at least one memory operably connected to the at leastone processor and storing instructions, wherein the at least oneprocessors execute the instructions, wherein the processor is adaptedto: receive a signal, wherein the signal is transmitted through aplurality of symbols, estimate phase noise for each of a plurality ofphase noise estimation durations included in the plurality of symbols ina time domain, wherein each of the plurality of phase noise estimationdurations is included in a cyclic prefix (CP) included in each of theplurality of symbols; and perform the phase noise compensation on theplurality of symbols in a time domain based on the estimated phasenoise.
 18. (canceled)